My friend , who ___on the International Olympic Committee all his life, is retiring next month.A served B.is serving C.had served D.has served
I don’t think Mary and Sue _____ before, ______?
The visiting professor _____ giving lectures to students ______ invited to meetings at times.
It’s nice _______ me with my lessons.
Please give my _____ to your teachers.
It’s ______ here; we can’t work long hours here.