The bargain they reached with their employers was to reduce their wage claim________a shorter working week.A．in return for B．in place of C．in honour of D．in charge of
---Do you like the city life or the country life? ---It’s hard to say. In the city there are _____interesting things, but in the country there is _____ pollution. A. less; more B. more; less
,
，其中
,我们把集合
,记作
，若集合
，则
的取值范围是 ▲ .
；