be (become) interested in
Li Hua spent too much time playing computer games and he fell behind others. As a good friend of his, I must do something to help him.
Firstly, I think it's very important for him to learn lessons well. He should spend most of his time on his study instead of computer games.
Secondly, I must tell him that playing computer games too much is bad for his health, especially for his eyes. So he must give it up. I can play more sports with him after school. Maybe he will become more interested in sports than computer games.
And then I'll ask him to concentrate more on his study. Of course, I will try my best to help him with all his subjects. I think I can do it in many fun ways and let him find much fun in studying. At the same time, I'll ask both his parents and our teachers to help him, too.
If I try these, I'm sure he will make great progress soon.