1x+x，5x2x中的分母含有字母是分式．故选A．
用所给词的适当形式填空。
1. The boy __________ (not have) any friends here.
2. Jim can __________ (play) the piano very well.
3. He is tired, let him __________ (have) a break.
4. What about __________ (visit ) the museum?
5. Juice and milk are _________ (health) drinks.
体感式游戏机
