Question

【题目】 The book was written in 1946, _________the education system has witnessed great changes.

A. when B. during which

C. since then D. since when

Answer 1

【答案】D

【解析】

试题分析：since when中的when指1946，since when指的是since 1946，即指“自1946年起”。注意不要误选C，如果将C改为and since then，则可选C。