—Have you ever _____ Mudanjiang to see the Jingbo Lake? —Yes, I have.
It is______ nice of you to say so.
Do you know the name of the boy _______ father is a doctor?
It was snowing hard_______we had to stay at home and watch TV.
________ is waiting for you over there. He wants to say thanks to you.
Heilongjiang is in the_______of China.