题目内容
The world is changing fast.I strongly believe that one will easily fall behind _______ he keeps on learning.?
| A.unless | B.if? |
| C.when | D.as |
A?
本题考查连词用法。根据句意,如果不学习很容易落下;所以选A项。
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题目内容
| A.unless | B.if? |
| C.when | D.as |