重点城市空气质量周报,目前主要有污染指数、首要污染物、空气质量级别三项内容。当污染指数在()之间时,空气质量为3级,属轻度污染。
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He didn't know which room ____.
How long have you____?
It is only in view of our long friendly business relations that we ____ you this accommodation.
What makes a meeting effective?
Talking to foreigners is fun if you____the right time and place.
Roy: ______ It 's getting late.
Ellen: Must you go soon?
What ’ s the meaning of money in the 5M ( ) .
Nancy: May I see your driving license and vehicle registration card, please?
Dick: ______.
You must pay import ____on certain goods brought into this country.
He treats it____a request for information.