问题 选择题

---We can't be successful _____  we keep on working hard.

---I agree with you.

A.if

B.because

C.unless

D.until

答案

答案:C

连词unless意为“除非……如果不……”,“除了……”,多引导一个否定意义的真实条件句,有时也可引导非真实条件句。

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