一 have you been in the sports club?—Since the first month I came to the school.
I heard from my pen pal yesterday, but I haven’t replied ______ her.
Did you know ______?
The number of people invited _____fifty, but a number of them ______ absent (缺席) for different reasons.
Mr. Wang was ______ because he was late for work. He is out of work now.
—Must we go there together at once?—______ you ______ he goes there, only one student is needed.