用所给的词的适当形式填空。（共10分，每小题2分）
1.Xiao Gang spends much time ______ ( play) computer games.
2. The little boy has only eight _______ (tooth) now.
3.Will you _______ (take) part in the long jump ?
4.I think I must do my best ___________ (improve) my English.
5. You must do sports to keep __________ (health).