Although it is not our normal _____ to give credit, this time I think we should consider the matter more closely.
All her time _______ experiments, she has no time for films.
---He will take you as well. ---But I’d rather he ______.
______ a pair of compasses, it is easy to describe a circle.
---Does your brother serve in the army? ---No, not now. But he ________ in the army for 8 years.
Everyone in our class works as hard as they can ________ to enter a good college.