A. I think a good talk with your friend is necessary for you. If it is you who make the mistake, you should say "sorry" to her. Communication is the best way to solve the problem.

B. Practice makes perfect. If you want to learn English well, you should practice more. Watching English movies is helpful. And you can remember English words before sleeping or after getting up.

C. You should drink much more water. You'd better have a day off and have a good rest. If necessary, a doctor can help you.

D. Don't get too excited before going to bed. You can drink a glass of milk, but not coffee. If it doesn't work, you'd better go to see a doctor.

E. You should pay more attention to your eating habits. You shouldn't eat much junk food.

Instead, you should eat more fruit and vegetables. Doing exercise every day can also help you.

F. You should be more self-confident. Try to join some clubs, take part in some parties, and make more friends. I'm sure you will not be so nervous as before.