Question

【题目】--- Mum, can I keep a pet?

--- No, _________ you have enough time to care for it.

A. as B. since C. if D. unless

Answer 1

【答案】D

【解析】句意：-妈妈，我可以养宠物吗？-不能，除非你有足够的时间照顾它。as因为，当…时候；since自从；if如果；unless除非。根据句意可知应选D。