问题补充：
I met him, I thought he was a serious man.
A. For the first time
B. The first time
C. It was the first time
D. By the first time
答案：
A. For the first time
(答案→)B. The first time
C. It was the first time
D. By the first time
解析：考查有关time的短语，For the first time意思“第一次”，the first time意思“初次”，It was the first time意思“这是第一次”，后面的句子要用过去完成时，句子意思“第一次我见到他，我认为他是个严肃的人”，句子I thought he was a serious man.是个宾语从句，省略了引导词that，所以选B
