—What do you think of a good friend?—Friends are like books—you don’t need a lot of them _________ they’re good.
---My mother is ill. ----_______ .
Mr Zhang is one of ____in our school.
– Are there cats in the classroom? –No, there aren’t .
The boy didn't run _______to catch the bus.
It is ____ useful book. ____ book is on her desk.