-What’s the matter with John? He has been sitting there for hours. -A postcard from his father an attack of home-sickness in him.
He _______ busy yesterday, or he _______ you with your experiment.
A teacher of English and class teacher _______ us something about volunteer workers.
It every day so far this month. I can't tell you if it tomorrow.
A student of Fudan University ___ Huang Yang, was reported ____ by his roommate, ______ the whole nation.
---Jack, you erase the blackboard today, __________? ---But I did it yesterday.