Question

I won't call you, ________ something unexpected happens.

1. A.
   unless
2. B.
   whether
3. C.
   because
4. D.
   while

Answer 1

A
句意：如果不出現(xiàn)意外情況，我就不給你打電話了。根據(jù)句意此處應(yīng)為條件。whether（不管）可以引導(dǎo)讓步狀語(yǔ)從句；because（因?yàn)椋�由于）引�?dǎo)原因狀語(yǔ)從句；while（當(dāng)……的時(shí)候，然而，雖然）引導(dǎo)時(shí)間和讓步狀語(yǔ)從句；unless (if…not)（除非，如果不）引導(dǎo)條件狀語(yǔ)從句，此句也可說(shuō)成：I won't call you, if anything unexpected doesn't happen.故選A。