句型转换：1.You must wait and open it later.（改为祈使句） ___ ___ ___it later!
2.I'll do my best to finish my homework.（改为同义句）
I'll ___ ___ ___ to finish my homework.
3.Both of them konw the answer.（改为否定句）
___ ___ them ___ the answer.
4.We must tell him the answer.（对画线部分提问）
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___ ___ we ___?