Question

【题目】(2017·北京卷) If you don’t understand something, you may research, study, and talk to other people _______ you figure it out.

A. because B. though C. until D. since

Answer 1

【答案】C

【解析】A. because 因为 B. though尽管 C. until 直到 D. since自从。句意：如果你无法理解某个东西，你可能会去研究，学习并和他人探讨直到你解决为止，根据句意可知选用until＂直到＂，再次引导时间状语从句，选C。