While in university, we were offered a number of afterschool activities to _____ our social skills.
— Who are you waiting for here?— The postman ______.
At present, we have come to sense that creativity is______ it takes to keep a nation highly competitive.
Close the door of fear behind you, and you ______ the door of faith open before you.
Regular reflecting is______ good habit. If so, you will make ______ great progress in your study.
The telephone _____ three times in the last hour, and each time it _____ for my sister.