Jack likes junk food very much. And he becomes fatter and fatter. 

Li Lei's English is very poor. He doesn't know how to learn it well.

 Wang Ping has trouble in falling asleep at night though he feels very tired. 

Xiao Mei doesn't know if she should still stay with her friend because there is some misunderstanding between them.

 Yang Yang is very shy. She is afraid of speaking to other people, especially the strangers. 

A. If you want to learn English well, you should practice it more. For example, read some English texts every morning and try to speak in English with your classmates or friends. 

B. You should eat more fruit and vegetables but not junk food. The most important thing is that you should do some exercise every day. 

C. You should drink lots of water and ask your doctor for help. 

D. You should try to relax yourself. Maybe you can listen to some light music when you can't fall asleep. Drink a glass of milk at night. It can help you fall asleep.

E. You must take some medicine and have a good rest. You'd better take some days off.

F. You should have a good talk with your friend. If it is your fault, you should say "sorry" to your friend. I'm sure your friend will understand you.

G. You should be more self-confident（自信的）. You can join in some parties, try to make more friends and talk with them.