He made a fire _______ himself _______ warm.
People hope that there will be _____ pollution in our country.
---Could you tell me when Mr Green _____ in Shanghai tomorrow?---Sure. When he _____, I’ll tell you in time.
Gesang hasn’t seen _____ football game since last year.
_____ years ago, people first began to drink tea in China.
_____ is our duty _____ the environment.