Try to spend as much time as you can___________, please.
Mr. Li is not here, and you’d better call him ____3 p.m. ____ 5 p.m. tomorrow.
There are quite a few old books on the shelf, but _____ of them is useful to teenagers.
---Whose purse is it? ---If it isn’t yours, it must be _________.
________ a lot of trees in this area, but now we can see a tall building instead.
--We can take a subway in Wuxi in 2015. ---Wow, _________! Will it pass our school?