Now the air in our city is _______ than it used to be．Something must be done to stop it．

 —Who is that boy?—Oh, he is Li Jing. He is ________ student in our class.

— What a traffic jam! I’m going to be late again.—Yes. The traffic now is _______than it used to be.

The Yellow River is the second          in China.

Remember, the _______ your practise speaking English, the _______ you will use it.