Dear Dr. Wise£¬

I'm a senior 3 student. Since I became a graduating student, I have been staying up late to finish piles of exercises. I often feel sleepy in class. As a result, I miss lots of key points and it usually takes me more time to finish my homework, which makes it difficult for me to concentrate on what I'm doing. What's worse, I haven't made any progress, which made me lose interest and confidence in studying. What should I do?

Sincerely,