Question

She says that she’ll have to close the shop ______ business improves.

She says that she’ll have to close the shop ______ business improves.

A. if
B. unless
C. after
D. when

为什么不能用C 和A,感谢

Answer 1

答案是B.
这取决于意义。
A.if：如果生意有起色，她将不得不把商店关了。（讲不通）同样C.D也是如此。