单项选择题
I am pleased to take（）to exchange views with you.
A.this opportunity B.a chance C.this time D.aperiod
单项选择题 Please leave the key under the door（）you go out.
单项选择题 We have kept（）our friendship by writing to each other, so we are true friends.
单项选择题 It（）that I met one of my old classmates on my way home yesterday.
