Question

对They are doing homework at present.中的they进行提问，改为特殊疑问句

1、Who are doing homework at present?
2、Who is dong homework at presnt?
是哪个，为什么呢？

Answer 1

因为 they 是比一个人更多 就是 plural
而整句话中的 sing/plural 要一致 所以用they 的时候 要用
who are doing homework at present

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Answer 2

应该是：
Who are doing homework at present
因为对they提问，they是复数，系动词只能用are

Answer 3

应该用who is doing homework at present?更合适些﹐因为提问的时候根本分不清是多少人在做homework﹐所以一般不会上来就用复数。
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