Question

I met Mr. Green ________ I was walking across the bridge, but I didn't say hello

I met Mr. Green ________ I was walking across the bridge, but I didn't say hello to him.
A. before
B. after
C. until
D. while

Answer 1

答案D
解析：本题考查时间状语从句的用法。before意为“在……之前”；after意为“在……之后”悔坦；until意为“直到……”；while意为“与……的同时”。从句辩前茄意知道while符合句子的意思。携察因此D为正确答案。