I see him, he looks sad.
A. Every now and then
B. Every now and again
C. Every so often
D. Every time
网友回答
A. Every now and then
B. Every now and again
C. Every so often
(答案→)D. Every time
解析：句意： 我每次见到他，他看起来都很难过。A. Every now and then不时地，常常；B. Every now and again偶尔，有时；C. Every so often偶尔，时常；D. Every time每次，每当，在这里是连词，后跟句子，引导的时间状语从句。根据句意故选D。