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A clean environment can help the city bid for the Olympics, which ______ will promote its economic development.
| A．in time | B．in turn | C．in return | D．in fact |
How can they learn so much they spend such a lot of time hanging about?
| A．although | B．when | C．before | D．until |
The students in the university are all taking courses to a degree.
| A．lead | B．leading | C．led | D．to be leading |
There is no in trying to talk George into joining us. He enjoys being alone.
| A．doubt | B．wonder | C．hope | D．point |
An advertisement is useful in it can persuade customers to but the kinds of goods in the shop.
| A．that | B．which | C．what | D．whether |
I don’t mind her criticizing me, but is how she does it that I object to.
| A．it | B．that | C．this | D．which |