Question

【题目】My mother has taught in this school________ she was twenty years old.

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

Answer 1

【答案】D

【解析】句意：我母亲从二十岁起就在这所学校教书。A. for为，后接一段时间；B. until直到；C. because因为；D. since自从，后接时间点。由句意可知D正确。