the children are having fun ( ) on the hill.play to play playing played

问题描述:

the children are having fun ( ) on the hill.play to play playing played

have fun in doing sth. 其中的in可以省略.即 have fun doing sth. 故选择C (playing)

playing

答案选 to play
孩子们很高兴地在山上玩。

playing
have fun doing sth.

have fun dong sth 开心于某事
选 playing