Please talk about the eight English tenses in detail and give examples of their specific usage in sentences? Are they eight or sixteen English tenses?

A summary of the 16 tenses in English grammar

Tense is an important grammatical category in English. It expresses actions or states of existence that occur at different times and the way in which actions occur or exist. . The time when the action occurs can be divided into four forms: present, past, future and past future. The way the action occurs can be divided into four forms: general, completion, progress and completion. Combining these time forms and action forms, the following 16 tense forms are formed (taking do as an example):

1. Simple present tense (do/does; is/am/are)

①Indicates the current situation, status and characteristics.

Example: He is a student.

He is a student.

② Indicates regular and habitual actions.

Example: He always helps others.

He always helps others.

③ Objective facts and universal truth.

Example: The earth moves the sun.

The earth moves around the sun.

④ Indicates an action that is to occur according to regulations, plans or arrangements. (Commonly used in train, bus, airplane or ship timetables)

Example: The next train leaves at 3 o'clock this afternoon. The next train leaves at 3 o'clock this afternoon. ⑤ Present of subject and subordinate: The present simple is often used to express future events in time, condition and concession adverbial clauses.

Example: If it rains tomorrow, we will stay at home.

If it rains tomorrow, we will stay at home.

④The present continuous tense is used with adverbs of frequency to express the speaker's emotional tone, whether it is positive or negative.

Example: He is always helping others.

He is always helping others. (Praise)

④The past continuous tense is used with adverbs of frequency to express the speaker's emotional tone, whether it is praiseworthy or derogatory.

Example: When he lived in the country, he was always helping the poor.

When he lived in the country, he always helped the poor.

4. Simple future tense

①The basic structure is will do.

Example: We will send her a glass hand-made craft as her birthday gift.

We will send her a glass hand-made craft as her birthday gift.

We will send her a glass hand-made craft as her birthday gift.

②When it means "intend to..., want to...", you can use am/is/are going to do.

Example: This is just what I am going to say.

This is just what I am going to say.

③ When it means "about to do", you can use am/is/are about to do. Emphasize what needs to be done in the near future or immediately.

Example: Don't worry, I am about to make a close examination on you.

Don't worry, I will do a close examination on you right away.

④ Two uses of "be to do":

a) It means "to plan or arrange for something to happen or to do something".

Example: She is to be seen in the lab on Monday.

You will definitely see her in the lab on Monday.

b) Things that should or should not be done (the tone is close to should, must, ought to, have to), expressing a commanding and persuasive tone.

Example: You are to go to bed and keep quiet, kids. Our guests are arriving in less than 5 minutes.

Children, you must go to bed and keep quiet, kids. Our guests will be arriving in 5 minutes.

5. Future continuous tense (will be doing)

Emphasizes the action or state of existence that is taking place at a specific time in the future.

Example: Don't worry, you won't miss her. She will be wearing a red T-shirt and a white skirt at that time.

Don't worry, you won't miss her. You won't recognize her. She will be wearing a red T-shirt and a white skirt.

8. Simple past tense (did; was/were)

① Indicates an action or situation that occurred at a certain time in the past.

Example: I bought some fruits yesterday.

I bought some fruits yesterday.

② Indicates past habitual actions.

would/ used to do: used to...

Example: The old man would sit on a bench in the quiet park and look at others for hours without doing anything or talking to anybody.

The old man used to sit on a bench in a quiet park, watching other people, for hours without doing anything or talking to anyone. People talk.

He used to visit his mother once a week.

He used to visit his mother once a week.

9. Present perfect tense (have/has done)

① Indicates that the action has been completed so far or has just been completed, emphasizing the impact on the present.

Example: I bought a new house, but I haven't sold my old one yet, so at the moment I have two houses.

I bought a new house, But haven't sold the old one yet, so now I'm two houses down. ② Indicates an action or situation that started at a certain time in the past and has continued to the present, and may continue. Continuous verbs are often used here.

Time adverbials often use since plus a past time point, or for plus a period of time, or by plus a present time.

Example: Great as Newton was, many of his ideas have been challenged today and are being modified by the work of scientists of our time. is being challenged and revised by the work of modern scientists.

10. Present perfect continuous tense (have/has been doing)

Indicates that an action started at a certain time in the past, has continued or repeated to this day, or will continue to future.

Example: We have been working on this project for over a month now.

So far, we have been working on that project for more than a month now.

11. Past perfect tense (had done)

① Indicates an action that has been completed or a state that has existed before a certain time or action in the past. It is what we often call "the past of the past".

Until then, his family hadn't heard from him for six months.

② It means an action or situation that started in the past, continued to the past, and may continue. Continuous verbs are often used here.

By the time I left the school, he had taught the class for 3 years.

By the time I graduated, he had taught the class for 3 years.

12. Past perfect continuous tense: had been doing

It means that it started in the past and continued to the past actions or situations. During this period, it has been carried out regularly without interruption, and may continue. Continue. Continuous verbs are often used here.

Example: The old clock had been being taken apart of and fixed up again for several times by my 10-year old son before I came back home.

Before I came home, My 10 year old son has disassembled and reassembled this old clock several times.

It means that the action started from a certain time in the past and continued to a certain time in the past and future. During this period, it has been carried out regularly and without interruption, and it is possible to continue.

Example: They said that by the end of the following month, the project would have been being worked for 3 years.

They said that by the end of the following month, the project would have been being worked for 3 years.

They said that by the end of the following month, the project would have been being worked for 3 years. It has been going on non-stop for 3 years.

Example: By the end of next month, the project will have been being worked for 3 years.

By the end of next month, the project will have been being worked for 3 years. It’s been 3 years.