Question

英语的疑问句，疑问词做主语则谓语动词一定单三吗？请举例，详解。如：who,when,what 等举例。谢谢。

Answer 1

who和what是可以作主语的，when做疑问词时，在句子中间一般只能作状语。
who和what在疑问句中作主语谓语动词用复数还是第三人称单数要看作主语的who或者what是第一二人称单复数还是第三人称单数：
Who are your classmates？谁是你的同班同学？很显然这里的who是第三人称复数；
Who does go to school on foot in your class？这里很显然是第三人称单数；
what做主语时,后面的动词用一般用单数的较多。如果后面接的表语是名词，那么谓语be根据表语决定。如：
What you said is important.
What we do now is (to) study hard.
What we need is knowledge.
What they want are some books.这个用的是复数形式。 when做主语一般只能用第三人称单数when this picture will be sent out hasn't been decided yet.只能用单数，即使把 this picture改成these pictures

Answer 2

　　疑问词分疑问代词和疑问副词，而只有疑问代词可以作主语，疑问代词有：what, who,whom,whose,which,，其中what, who,which可以做主语，至于谓语用单数还是复数，取决于语境，即上下文。举例如下：
　　Who is in the room?　谁在房间里？（问者不清楚房间里一人还是多人）
　　Who are in the room?　都谁在房间里？（问者比较肯定房间里有至少两人）
　　What is in the box?　盒子里是什么？（问者不知内部情况）
　　What are in the box?　盒子里都有些什么？（问者确信里面不知一样或一件东西）
　　Which is your book?　哪本是你的书？
　　Which are your books?　哪些是你的书？

Answer 3

不一定，根据不同情况。
Who is he? Who are they?
When does she leave? When do they have lunch?
What do you mean? What is procrastination?
谓语动词是否是单三并不仅仅看疑问词，而是要看整个句子的意思。