Before the tourists set off , they spent much time setting a limit _____ the expenses of the trip.
If we can keep ____ this speed, we'll arrive there in two or three hours.
The Great Wall was built to keep ____ the invaders.
I should very much like to have gone to the party, but______.
---Those shoes won't_____for mountain-climbing. ---_____this pair be OK?
Now Robert, a football fan in our class, _____ rome of his daily allowance given by his parents in order to buy a new football.