Joke Collection Website - Bulletin headlines - Help me translate the following article.

Help me translate the following article.

Mimi,Micky and their classmates are on a field trip for social study. They came to a hospital. Rabbit put up a quick sign in front of the hospital. She wanted to tell everyone, "Please keep quiet!" " They came to a busy street. The dog also put up a sign telling everyone, "Don't cross the road!" " Mimi put up a sign to tell everyone, "Be careful!" (Then) they came to a beautiful park. The panda put up a sign telling everyone, "Don't trample on the lawn!" " Mickey pointed out his sign (which said), "No littering!" " Mickey feels hungry. He ate a banana and then threw the banana peel on the ground. What did Mickey do wrong? What will his classmates do now?