Question

Bob promises to join in the football match ______ he has to help his parents on the farm.

A．if

B．as

C．unless

D．when

Answer 1

C

考查从句的连接词。句意“鲍勃答应参加足球比赛，除非他不得不要帮爸妈干农活。”A“如果”；B“当；正如”；C“除非”；D“当”。根据句意可知，用unless。故选C。