Preposition Challenge New Gold 2 (Advanced 2) UNIT 1
I'm going out for a walk. I can't concentrate _____ my homework right now. (FROM | ON | FOR | WITH | TO | AT | IN | OF)
on
We need to concentrate our efforts _____ finding the solution for this problem. (FROM | ON | FOR | WITH | TO | AT | IN | OF)
on
Are you sure it's OK for us to stay the night? We don't wish to impose _____ you. (FROM | ON | FOR | WITH | TO | AT | IN | OF)
on