You ______ buy a gift, but you can if you want to.

单项选择题______ before you leave the lab.

单项选择题I was impressed______the efficiency of the work done in the company.

单项选择题The idea came to me when I ______ with him.

单项选择题—Is Blake still absent from class —I think he______be punished if he goes on with it.

单项选择题The reason why the traffic was stopped was the bridge ______ was broken.