The children are having a good time,

问题描述:

The children are having a good time,
_____ with sand others with toys.
A.some of them playing B.same of them are playing
C.some of them D.who playing
为什么,请解析,

play在作非打球的意思时候是不及物动词
翻译句子是
他们中的一些玩沙子和玩具