—_____ does Kangkang meet his friends? —Four times a month.A. When B. How long C. How often
Now teenagers are very busy with their schoolwork all the time and they have _____ time to do sports.
I never doubt ________ his advice is of great _________ to me.
—Is David coming by train?—He should, but he not. He likes driving his car.
US First Lady Michelle Obama encouraged students to study abroad in her when visiting Peking University on March 22, 2014.
Be quick, ___________ we’ll be late for the meeting.