单选题
I have kept up a friendship with a girl whom I was at school（ ）twenty years ago.
Aabout
Bsince
Ctill
Dwith
正确答案
答案解析
该题考查定语从句。该句中whom I was...ago是定语从句修饰a girl，而在定语从句中谓语动词的宾语不能直接是a girl，即要接一个介词with，其他选项不符合题意，故答案为D。