---I feel tired.---Why don’t you go to bed early for ___ nights?
Which floor do you live ______ this building?
The post office is about five kilometers ______ our school.
The maths problems are too hard, only ______ people can work them out.
---______ does he go to Guangzhou on business? ---Three or four times a year.
I always go to the lake ____ the aftenoon, but Kate goes there ____ the night of Monday.