Question

【题目】We won't be able to learn English well we learn enough words by heart and do enough reading.

A.as

B.once

C.when

D.unless

Answer 1

【答案】D

【解析】

考查从属连词。句意：除非用心多记单词和做大量的阅读，否则就不能把英语学好。A. as由于；B. once一旦；C. when当……时候；D. unless除非，如果不。分析句子可知，空白处表“除非”，用unless。故选D。