问题

Tom, you won’t make much progress_________ you work really hard.—Ok, I will try my best.

A:if
B:though
C:unless
D:when;

正确答案是：

同类题型

This is 3-Dprinter. And this is an artificial (人工的) ear. Canyou believe that scientists printed this artificial ear by this 3-D printer

The Medical Research Council said it could not _____ use of the new drug without further tests.

I was tired out, so I stopped the car a short rest.

The most satisfying life is one ______ you know thethings you’re interested in and pursue it in your own way

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