Bob promises to join in the soccer match ____he has to help his father on the farm.A.if B.unless C.a
题目
Bob promises to join in the soccer match ____he has to help his father on the farm.A.if B.unless C.as D.when
为什么呢?
答案
unless 表示除非.整句的意思是,除非Bob必须要去农场帮他父亲,他就会参加足球赛.
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