Question

【题目】Everyone should do a part _________we can have a clean and comfortable environment.

A. untilB. unlessC. thoughD. so that

Answer 1

【答案】D

【解析】

句意：每个人都应该尽一份力，这样我们才能有一个干净舒适的环境。A. until直到；B. unless除非；C. though尽管；D. so that以便。so that引导目的状语从句，结合句意可知，答案为D。