If you are travelling _______the customs are really foreign to your own, please do as the Romans do.
The second season of A Bite of China ________ for a month. It turns out to be the most popular documentary.
Have you ____ joined in a dragon boat race?—Yes,I have.
_____ is my sister. ______ name is Tina.
What do you think of your boss?—He always work hard and he is ____________ late for work.