English composition about park slogans

There are many signs in the parks. Some are used to warn the people, such as "no barbecues". Some are used to protect the plants in the park., such as "don't walk on the grass " .All the signs are small but conspicuous, so that people can not neglect them .But why do the parks need the signs ?in my opinion, it's because people can not be aware of the bad habits they have . their behavior had damaged the beauty of the park. So, I think we should be more conscious.