If you sleep less than 7 hours a day, you are more to catch a cold.
There is a limit ____ my patience.
How can we ____ all these flies in the kitchen?
If you ____ do as I tell you , you ____ go to the party .
Li Ling was a diligent boy . He ____ go to school though it was raining hard .
The work ____ be finished in such a short time .