–Sorry, Professor Smith. I didn’t finish the assignment yesterday. --Oh, you _____ have done it as yesterday was the deadline. A. must B, mustn’t C, should D. shouldn’t
I think they failed to accomplish the task, ______?
You might as well expect a river to flow backward ____ us carrying out the plan.
________had the worker who was badly injured in that accident stopped breathing and died________ doctors arrived.
So fast _____it is difficult for us to imagine its speed.
You should know _______to spend all your money on those impractical fancy goods.