问题

One can’t be successful ________ he or she keeps working hard.—I agree with you.

A:although
B:unless
C:because
D:if;

正确答案是：

同类题型

Water can absorb and give off a lot of heat without big changes in temperature, this creating a _____ environment. [ ]

Jill couldn’t resist ________ jokes on his partner. [ ]

One solution to this problem now is sustainable development.

He won the first prize in the competition and we were _______ him.

Listen! Somebody is ___________ at the door.—Don’t answer the door! Mom doesn’t let us do it while she is out.