Question

【题目】Mary is serious about her study. She won't go to bed ________ she finishes all her homework.

A. if B. because C. when D. until

Answer 1

【答案】D

【解析】试题分析：句意：Mary对学习很认真，她直到完成作业才上床睡觉。直到---才是not---until。故选D。