What the police want to know is when you entered the room.
The trouble is that we are short of funds.
This is what we should do.
That's why I want you to work there.
His first question was whether Mr. Smith had arrived yet.
as if, as though, because也可用來引導補語子句。
She seems as if she had done a great thing.
It is because you eat too much.
主語是idea, notion, proposal, suggestion, request等名詞時,作補語子句的動詞為原形動詞或should+原形動詞。
My suggestion is that we (should) go and help him.
Our only request is that this should be settled as soon as possible.