Question

【题目】The new policy allows a couple to have a second birth____either is an only child.

A. if only B. on condition that

C. unless D. until

Answer 1

【答案】B

【解析】句意：新政策允许一对夫妇可再生一个孩子，条件是双方有一个是独生子。If only但愿；on condition that条件是；unless除非，如果不；until直到。故选B。