Philosophical inspirational talk: never giving up is the best character of pursuers.

1, learn, learn, learn again! Study and then know enough.

2. Is it really disgusting to see people like us who are physically and mentally healthy and have no sexually transmitted diseases?

3, people are not afraid to walk in the dark, they are afraid that there is no light in their hearts.

4, don't do evil, don't do good. Only virtue and virtue can serve others. -Liu Bei

Emotional debt, like the sea of time, is beyond our reach.

6. The height of thought determines the height of action, and the height of culture determines the height of enterprise.

7, the road to the king must be bumpy, please step on the thorns to the throne of the king.

8. If the building of career lacks the pillar of perseverance, it can only be a castle in the air.

9. There is only one kind of heroism in life, and that is to love life after recognizing the truth of life.

10, what you want, think clearly, choose and cherish, just like your marriage.

1 1, the highest level of watching ghost movies: I fell asleep when I watched it.

12. People who made great achievements in ancient times not only had talent, but also had persistent determination. -Su Shi

13, if you are ambitious, you will live for a hundred years without ambition!

14. The sun is new every day. Do you work hard every day?

15, life is like a song. Singing with your heart will be beautiful.

16, patience and struggle can conquer fate.

17, I would rather forgive others myself than wait for others to forgive myself.

18, people who are willing to take risks.

19, travelers often arrive, and doers often succeed.

20. When a person is indifferent to you, please leave quickly. No one has the obligation to please others.

Never give up.

1, don't be afraid to lose something beautiful for a great cause. Kenny Rogers

My highest principle is: Don't give in no matter what difficulties you meet. Madame Curie

People say that life is short, and I think they make life so short. Because they are not good at using life, they in turn complain that time passes too fast; But I think, as far as their lives are concerned, time passes too slowly. -Rousseau

4. Those who dare not take risks have neither mules nor horses; People who take excessive risks will lose mules and horses. -rabelais

5, failed, we have to tell people around us that we are living well now, we are making progress through hardships, we will continue to work hard, and we will eventually have a successful tomorrow!

6. As long as you don't give up, failure won't be a foregone conclusion. anonymous

7. Whether in good times or bad times, life is an endless struggle with all kinds of difficulties, a battle with too many people. Tagore

8. The ideal wind raises the sails of life; The extreme of struggle raises the ideal banner.

9. People who are interested in a certain cause, rather than fishing in the forest, might as well settle for the second best and make a network, that is, they should be fully prepared for the abilities needed for this certain cause. -Zou Taofen

10, life is like a market, where people gather, but stay soon; Life is like an inn, passers-by stop and walk again. -Aho Brown

A man's failure is a direct result of himself. James allen

12, this is not a question of whether there is food to eat, but because there is a fire burning in my heart, and this indomitable fire is working in my body. -(Japan) Hara Yiping

13. According to my observation, most people succeed when others ignore them. Ford

14, lost cattle and sheep can be recovered; But the lost time is irreparable. -Chaucer

15, the glory of life lies not in never giving up, but in being able to fight again and again. -Napoleon

16, life is based on time, wasting other people's time is equal to murder for money, and wasting your own time is equal to chronic suicide. -Lu Xun

17, no wind and rain, no tree can grow; It is difficult to make steel without a hundred tests. -Lei Feng

18, people's life can't be smooth sailing, and growth is bound to go through the baptism of wind and rain. Take a confident step and never give up!

19, an inch of time and an inch of gold are hard to buy. -Proverbs

20. The struggle has been going on every day since the beginning of mankind. -Sun Yat-sen

2 1, human life is very short. The short years require me to have a good understanding of the process of life ... Gorky

22. If you don't come back in your prime of life, it's difficult to get up in the morning. Give yourself timely and appropriate self-encouragement, and time and tide wait for no man. Tao Qian

23. Faith blooms the flower of success. Don't let tomorrow's dreams be eclipsed by yesterday's depression. You know, dusty gold will shine only after the passage of time and the blow of wind and rain!

If there is anything that needs to be done tomorrow, you'd better start now. Franklin

25. Failure is the mother of success!

26. True agility is a very valuable thing. Because time is the standard to measure career, for example, money is the standard to measure goods. -Christopher bacon

27, tomorrow after tomorrow, how many tomorrows! Waiting for tomorrow, everything will be wasted. The world is tired of tomorrow, and tomorrow will be infinitely experienced. The morning and evening are rolling, and the water flows eastward. Today's ancient days are long and the west is falling. What will tomorrow be like in a hundred years? Please listen to my song tomorrow. -Wen Jia

28. The clock ticks with the movement of the hands: "second" is the soldier marching in the heroic procession, "minute" is the sergeant, and "hour" is the brave officer who leads the team to the front. So when you are bored thinking, please remember that there are thousands of horses in your palm; You are their commander in chief. When looking back on them, we might as well ask ourselves whether they played the greatest role in the battle. -Fei Cai Johnson

There are many difficulties in growing up. Please don't doubt yourself. Weave a peerless laurel with your own hands and wear it on yourself.

Life is too short to do. I have to race against time. Edison

3 1, the glory of life lies not in never failing, but in being able to fail and fight again and again. -Napoleon

In the stormy waves of life, we often learn from the captain and throw away the heavy cargo under the storm to reduce the weight of the ship. -Balzac

33, Tian Xingjian, the gentleman is constantly striving for self-improvement. -Zhouyi

34. Difficulties are the teacher of life and the best school.

35. The greatest glory in life lies not in never failing, but in being able to rise again and again. Goldsmith

36. Difficulties are like springs. Strong is weak, weak is strong. anonymous

37. Today is life, today is motivation, today is behavior and today is creation. -Li Dazhao

38. A life of trial and error is not only more brilliant but also more meaningful than an idle life. -Bernard Shaw

39. The so-called living person is one who constantly challenges and climbs the dangerous peak of fate. Hugo

I don't admit defeat, and I will never admit defeat. -(Japan) Hara Yiping

4 1, Tian Xingjian, the gentleman strives for self-improvement; The capacity of the earth is limited, so a gentleman must constantly cultivate his own virtue to undertake the world. -Zhouyi

42. Pain often makes the weak world-weary, but it makes the strong more awake and energetic. anonymous

43. Unfortunately, time is a pity. For example, water loss should be treated as a secret of the World Expo to help make contributions. -Yan Zhitui 1 1 wasting time is called wasting time, and wasting time is called living. Younger

44. Where there is a will, there is a way. One hundred and twenty Qin Guan will eventually lead to Chu, and painstaking efforts will not be made. -Pu Songling

45. Who said that we must take someone else's road? Who says there is no pain behind glory? As long as we don't give up for our dreams, we will never stop. -Qu Wanting

46, time is a lovely lover, how much I love you, telling you every minute; Work, create, don't waste your life. -Yusha

47. Courage and wisdom are a magic weapon for a person to overcome difficulties and setbacks.

48. Our greatest weakness lies in giving up. The only way to succeed is to do it all over again. Thomas Edison

Never give up this famous maxim.

1. Today is life, today is motivation, today is behavior, and today is creation. -Li Dazhao

2. The glory of life, inspirational movies, lies not in never giving up, but in being able to pounce again and again. -Napoleon

3, Tian Xingjian, the gentleman is constantly striving for self-improvement. Drop your own sweat and eat your own food. Do your own thing, rely on people and ancestors, not heroes. "-Tao Xingzhi, ancient and modern, Chinese and foreign, anyone who has achieved something and made a difference to mankind is the result of down-to-earth and hard climbing." -Qian Sanqiang.

4. Be persistent, especially confident! We must believe that our talent is used to do something, and this kind of thing must be done no matter what the cost-Madame Curie.

5. Suffering is like a dark cloud. When you look from a distance, you can see that it is dark, but when you are there, it is only gray. -Li Xite's Chang Gung Hang

6. Don't suffer from people who don't know themselves and people who don't know others. -Confucius

7. Good things come from difficulties, and teenagers don't ask for easy things. -Li

8. Only confident people can immerse themselves in life with confidence everywhere and realize their will. Gorky

9. Adversity gives people precious opportunities to hone. Only those who can stand the test of the environment are truly strong. Great men since ancient times have struggled out of adversity with indomitable spirit. -Kōnosuke Matsushita

10, the ideal wind raises the sail of life; The extreme of struggle raises the ideal banner.

1 1, I think the mouse's brain is worthless, and it only knows how to drill holes. If this hole doesn't come out, everything will fail. -Chaucer

12. Fate favors those who are prepared.

13. Running an enterprise is the simultaneous operation of many links. An idea is needed to decide the whole failure. -Kōnosuke Matsushita

14, countless people fail because their work is not thorough, and they often stop only one step away from success. -Shakespeare

15, Tian Xingjian, the gentleman strives for self-improvement; The capacity of the earth is limited, so a gentleman must constantly cultivate his own virtue to undertake the world. -Zhouyi

16, the glory of life lies not in never failing, but in rising again and again. -Napoleon

17, the clock ticks as the pointer moves: "Seconds" is a soldier marching in heroic procession, "Minutes" is a non-commissioned officer, and "Hours" is a brave officer who charged ahead. So when you are bored thinking, please remember that there are thousands of horses in your palm; You are their commander in chief. When looking back on them, we might as well ask ourselves whether they played the greatest role in the battle. -Fei Cai Johnson

18, difficulties contain victory, and failure breeds success.

19, pain often makes the weak world-weary and suicidal, but it makes the strong more awake and energetic.

20. Even if you fall a hundred times, you should stand up a hundred times. -Zhang Haidi

2 1, real agility is a very valuable thing. Because time is the standard to measure career, for example, money is the standard to measure goods. -Christopher bacon

22. Since you have chosen a distant place, you only care about hardships!

23. No one can find the truth without experiencing failures and setbacks.

24, wasting time is called wasting time, stripping time is called life. Younger

We learn much more from failure than from success. smile

26. A great attempt is magnificent even if it fails. Vincent lombardi

27. Failure in life is our best nourishment. With failure, we can know the reason of failure, learn from it, and walk more smoothly in the future life journey. Failure is not terrible. The terrible thing is that you will be devastated after failure. Failure is not hateful. What is hateful is that I don't know why I failed after I failed!

28. A noble heart should bear disasters rather than avoid them, because bearing disasters shows noble will, while avoiding disasters shows inner cowardice. -Aretino

29. Success without many failures is rare.

30. People's strength in willpower and militancy is often one of the important reasons for their success or failure. -Hardy

3 1, people who have not experienced adversity do not know their own strength. -Jonson "Really Reliable"

Don't be afraid to lose something beautiful for a great cause. Kenny Rogers

33. The brilliance of youth, the key to ideal, the meaning of life, and even the survival and development of mankind are all contained in these two words ... Struggle! Only by struggling can we heal the wounds of the past; Only struggle is the hope and light of our nation. Marx

If you are afraid of failure, you will never succeed.

35. The difficulty lies in the talent, not only there will be. -Ouyang Xiu's "Han Gong Yue Ancient Hall"

36. Bao Jianfeng comes from sharpening, and plum blossom fragrance comes from bitter cold.

37. The more you move forward, the more frustrated you are. -Sun Yat-sen's The Founding of the People's Republic

38. A soldier who wants to be a marshal is not a good soldier.

39. Don't be complacent because of good luck, and don't be depressed because of bad luck. A truly strong person is good at finding shadows from prosperity, finding light from adversity, and always calibrating his goals. Ibsen

40. A great dead man never fails. byron

4 1, life is short, there are too many things to do, and we have to race against time. Edison

42. I have struggled for more than 50 years and devoted myself to the development of science. One word can tell the most difficult feature of my work, and that word is "failure". -Thomson

43. Those who don't learn from failure will have a long way to success. -Napoleon

44. There is no mountain you can't climb, and there is no river you can't cross.

45. A person who is determined to make great achievements must know how to limit himself, as Goethe said. On the contrary, people who want to do everything can't do anything and will eventually fail. -Hegel

46. Struggle is the father of everything. -Tao Xingzhi's letter to Xiao Sheng

47. Where there is a will, there is a way.

48. You also need a kind of self-confidence. Only this kind of self-confidence can support you to face greater difficulties.

If no one teaches us the lesson of failure, we will accomplish nothing. The trajectory of our thinking is to choose between right and wrong, and the frequency of wrong choice and correct choice is equal. Lewis thomas

50. Make up your mind not to be afraid of sacrifice, overcome all difficulties and strive for victory. -Mao Zedong's "Yu Gong Yi Shan"

5 1, where there is a will, there is a way. 120 Qin Guan will eventually return to Chu, and everyone who helps him will not do it. -Pu Songling

52, failure, not afraid of setbacks, not afraid of blows-whether it is personnel, life, technology, academic blows. -Fu Lei

53, tomorrow and the day after tomorrow, how many tomorrows! Waiting for tomorrow, everything will be wasted. The world is tired of tomorrow, and tomorrow will be infinitely experienced. The morning and evening are rolling, and the water flows eastward. Today's ancient days are long and the west is falling. What will tomorrow be like in a hundred years? Please listen to my song tomorrow. -Wen Jia 3 As far as I can see, most people make achievements when others ignore them. Ford

54. Suffering trains some people and destroys others. -Fuller's words of wisdom

55. Without wind and rain, you can't grow into a big tree; It is difficult to make steel without a hundred tests. -Lei Feng

If there is anything to be done tomorrow, you'd better start now. Franklin

57. I never knew what depression was. If I fail, I will come back. The future is created by myself. -Xu Teli

58, hardships, Yu Yu Yu Cheng.

59. There is no such thing as failure for indomitable people. Bismarck

60. You will never come back in your prime, and it is difficult to get up in the morning. It is timely to encourage yourself, and time waits for no one. Tao Qian

6 1, lost cattle and sheep can be recovered; But the lost time is irreparable. -Chaucer

62. The ups and downs are all nutrition, and success and failure are all experience.

63. An inch of time is worth an inch of gold, but an inch of gold can't buy an inch of time.

64. Those who never win seldom fail, and those who never climb seldom fall. -Whittier

65. My highest principle is: Don't give in no matter what difficulties you encounter. Madame Curie

66. Be brave to be yourself, be unique and unwilling to be others-Lin Yutang

67. Difficulties are the teacher of life and the best school.

68. A person's life is short. The short years require me to have a good understanding of the process of life ... Gorky

69. Difficulties are like springs. Strong is weak, weak is strong.

70. If you don't care when you use it, it will be damaged; If you are not careful, you will fail.

7 1. Thank God for not making me a clever craftsman. My most important discovery was inspired by failure. David

72. Failure 19 times and success 20 times is called persistence.

73. My most important discovery was inspired by failure. David

74. Good luck is admirable, but overcoming bad luck is admirable. This is a famous saying of seneca. -Bacon's bad luck

75. A person who loses confidence after being hit will always be a loser. Maugham

76. Life is based on time. Wasting other people's time is equal to murder for money, and wasting your own time is equal to chronic suicide. -Lu Xun

77. I never want to give up the life I struggled for. I attach great importance to the experience gained in the struggle, especially the pleasure gained after overcoming difficulties. A person will feel useful and comfortable only after going through difficulties first and then stepping into wealth. Edison

78. The lessons of failure are the lessons of success.

79. The glory of life lies not in never giving up, but in being able to pounce again and again. -Napoleon

80. When a person calmly suffers one major misfortune after another, the beauty of his soul shines out. This is not because he has no feelings about it, but because he is a noble and brave man. -Aristotle's Nicomachean Ethics

8 1 Failure is the mother of success. Phillips

82. No one is perfect and no one is indispensable. Everyone has weaknesses in one way or another. This weakness will ease his grief when he fails. -Labroue's ear

83. The failure of millions of people is the failure of doing things incompletely; Often one step away from success, and then it ends. -Shakespeare

84. As long as people have faith and pursuit, they can endure any difficulties and adapt to any environment. -Ding Ling

Be careful when you are lucky, and be patient when you are unlucky.

86. In the face of failure and frustration, laugh it off as optimism and self-confidence, and then the courage to rally.

You will never be a failure unless you stop trying. Mike ditaka

If we admit defeat too easily, we may not realize that we are very close to being right. sirkarl raimund popper

89. Since the beginning of mankind, struggles have been going on every day. -Sun Yat-sen

90, the defeat of gold, bribe your ears, make friends with your ears. —— Wang Fuzhi

9 1. If you want to finish something in a hurry to speed up, you will always fail. -Aesop

92. One failure can only prove that our determination to succeed is strong enough. Bove

93. Disaster is a real touchstone for a person. -Beaumont

94. Time is a lovely lover. I tell you how much I love you every minute. Work, create, don't waste your life. -Yusha

95. One hundred studies must be identified first. -Zhu

96. Perseverance and repeated servants. -Sun Yat-sen

97, bad luck is full of hope, good luck does not forget the worry, in order to bear the misfortune calmly. -Horace "Song"

98. Whether in good times or bad times, life is an endless struggle against all kinds of difficulties, a battle that is outnumbered. Tagore

99. Our dashed hopes, aborted talents, failed careers and frustrated ambitions are often called jealousy. -Balzac

100, managers should have the courage to try and make mistakes and strive to improve; We should not be afraid of risks and stand still. Graham Clarke

10 1, drop your own sweat and eat your own food. Do your own thing, rely on people and ancestors, not heroes. "-Tao Xingzhi

102. Worry and fatigue can bring prosperity, while leisure can lead to death. —— Ouyang Xiu

103, mortals are unreliable. If they depend on it, they will be defeated by it. It is inevitable that a good swimmer will drown and a good rider will fall. -Donglugu crazy life

104, you need a kind of courage, only this kind of courage will not let the difficulties leave a shadow in your heart.

105, no wind and rain, no tree can grow; It is difficult to make steel without a hundred trials. -Lei Feng

106, time is rare and easy to lose. -Jia Yi

107, what is gain and loss? The essence of life is excitement. The fruits of excitement are gain, loss, gain, gain, loss and gain by losing things. This is a great loss.

108, you need a strong person. Only this strong person can make you face up to the difficulties you are facing.

109, most people are conservative and don't believe in new things easily, but they can tolerate many failures in reality. -Carlisle

Fire can test real gold, and adversity can test the strong. -seneca is God's will.

1 1 1. Optimism predisposes you to happiness and health, while pessimism predisposes you to despair, illness, failure, melancholy, loneliness and timidity.

1 12, time is a pity, like lost water, when the Expo is kept secret, in order to help the cause. -Yan Zhitui

1 13, Phillips famously said, "Failure is the mother of success".

When failure has become a habit, success will come

1 15, you must think twice before you succeed. Once a decision is made, go all out resolutely and do nothing for fear of failure.

1 16. Among all the failures, trying to make one-liners is not the biggest failure, but it is even worse to talk sloppily. -Lando

1 17. A wise man will never sit down and lament for failure. They must look optimistically for ways to save them. -Shakespeare

1 18, you may be disappointed if you lose; But if you don't try, then you are doomed to fail. beverly sills

1 19. No matter how carefully you think, if you are careless, you may fail. No matter how exquisite your skills are, you won't succeed if you lack sincerity. —— Gu Tuhe

120, people say that life is short, and I think they make life so short. Because they are not good at using life, they in turn complain that time passes too fast; But I think, as far as their lives are concerned, time passes too slowly. -Rousseau

12 1 at all times and in all countries, all people who have made achievements in their careers and made a difference to mankind are the results of down-to-earth and hard climbing. -Qian Sanqiang

122, a theory that has not been tested by practice, no matter how beautiful it is, will lose its weight and will not be recognized; Practice that is not based on weighty theory is doomed to failure. Mendeleev

123, Tian Xingjian, a gentleman strives for self-improvement.

124, our biggest weakness is giving up. The only way to succeed is to do it all over again. Thomas Edison

Never give up reading famous sayings

Never give up reading famous sayings

1. Our greatest weakness lies in giving up. The only way to succeed is to do it all over again. Thomas Edison

2, an inch of time and an inch of gold, an inch of gold is hard to buy. proverb

If there is anything to be done tomorrow, you'd better start now. Franklin

4. Faith blooms the flower of success. Don't let tomorrow's dreams be eclipsed by yesterday's depression. You know, dusty gold will shine only after the passage of time and the blow of wind and rain!

This is not a question of whether there is food, but a fire burning in my heart, and this indomitable fire is working in my body. (Japan) Yuan

6, Tian Xingjian, the gentleman is constantly striving for self-improvement; The capacity of the earth is limited, so a gentleman must constantly cultivate his own virtue to undertake the world. Zhouyi

7. People say that life is short. I think they make life so short. Because they are not good at using life, they in turn complain that time passes too fast; But I think, as far as their lives are concerned, time passes too slowly. Rousseau

The greatest glory in life lies not in never failing, but in being able to rise again and again. oliver goldsmith

9. Courage and wisdom are a magic weapon for a person to overcome difficulties and setbacks.

10, life is short, there are too many things to do, and we have to race against time. Edison

1 1. The glory of life lies not in never giving up, but in being able to fight again and again. Napoleon

12, the struggle has been going on every day since human beings. Sun Yixian

13, time is a lovely lover, how much I love you, telling you every minute; Don't waste your life on labor creation. Yusha

14, time is a pity, like water flies, when the Expo is kept secret to help the cause. Yan Zhitui wasting time is called wasting time, and wasting time is called living. Younger

15, who said that we must follow someone else's path, who said that there is no pain behind the glory, as long as we don't give up for our dreams, no matter how hard it is, we will not stop. Wantingqu

16, a person's life is very short, and the short years need me to understand Gorky's life process.

17. Difficulties are the teacher of life and the best school.

18, the day after tomorrow, how many tomorrows! Waiting for tomorrow, everything will be wasted. The world is tired of tomorrow, and tomorrow will be infinitely experienced. The morning and evening are rolling, and the water flows eastward. Today's ancient days are long and the west is falling. What will tomorrow be like in a hundred years? Please listen to my song tomorrow. Wen Jia

19, pain often makes the weak world-weary and suicidal, but it makes the strong more awake and energetic. anonymous

Failure will not be a foregone conclusion as long as you don't admit defeat. anonymous

2 1, my highest principle is: never give in no matter what difficulties you encounter. Madame Curie

There are many difficulties in growing up. Please don't doubt yourself. Weave a peerless laurel with your own hands and wear it on yourself.

23. A life of trial and error is not only more brilliant but also more meaningful than an idle life. Bernard Shaw's

24. Lost cattle and sheep can be recovered; But the lost time is irreparable. Chaucer

25. Difficulties are like springs. Strong is weak, weak is strong. anonymous

The glory of life lies not in never failing, but in being able to fail and fight again and again. Napoleon

27. People who are interested in a certain cause, rather than fishing in the forest, might as well settle for the next best thing and make a network, that is, they should be fully prepared for the abilities required by this cause. Zou Taofen

28. Without wind and rain, you can't grow into a big tree; It is difficult to make steel without a hundred tests. Lei Feng

29. A person's failure is a direct result of himself. James allen.

30. Heaven is healthy, and gentlemen are constantly striving for self-improvement. Zhouyi

3 1, life is like a market, where people gather, but stay soon; Life is like an inn, passers-by stop and walk again. Ahobran

32. Where there is a will, there is a way. One hundred and twenty Qin Guan will eventually lead to Chu, and painstaking efforts will not be made. Pu Songling

33. You will never come back in your prime, and it is difficult to get up in the morning. It is timely to encourage yourself, and time waits for no one. Tao Qian

34. The ideal wind raises the sails of life; The extreme of struggle raises the ideal banner.

Don't be afraid to lose something beautiful for a great cause. Kenny Rogers

36. Life is based on time. Wasting other people's time is equal to murder for money, and wasting your own time is equal to chronic suicide. Lu Xun

37, failed, we have to tell people around us that we are living well now, we are making progress through hardships, we will continue to work hard, and we will eventually have a successful tomorrow!

38. The so-called living person is one who constantly challenges and climbs the dangerous peak of fate. Hugo

39. The clock ticks with the movement of the hands: the second is a soldier marching in the heroic ranks, divided into non-commissioned officers, and the hour is a brave officer who leads the team to the front. So when you are bored thinking, please remember that there are thousands of horses in your palm; You are their commander in chief. When looking back on them, we might as well ask ourselves whether they played the greatest role in the battle. Fitzgerald Johnson

40. True agility is a very valuable thing. Because time is the standard to measure career, for example, money is the standard to measure goods. Frebet Ken

4 1 Whether in prosperity or adversity, life is an endless struggle with all kinds of difficulties, a battle with a few people. Tagore

42. Those who dare not take risks have neither mules nor horses; People who take excessive risks will lose mules and horses. Rabelais

I don't admit defeat, and I will never admit defeat. (Japan) Yuan

44. In the stormy waves of life, we often learn from the captain and throw away the heavy cargo under the storm to reduce the weight of the ship. Balzac

45. Failure is the mother of success!

According to my observation, most people make achievements when others are idle. Ford

47. Today is life, today is motivation, today is behavior and today is creation. Li Dazhao

Never give up, celebrity quotes never give up, inspirational quotes never give up.