Hey, you haven’t been acting like yourself . Everything OK ?——。

My sister is_____ young_____ go to school.[ ]

What’s the noise ? It sounds as if it comes from upstairs. –______. It must be the window-cleaner working , next door.

Most scientists seem to agree that ________ certain limit should be set on ______sale of cars to ease air pollution.

.____me that you choose,so long as you finish the job on time.