.A reward of 1,000 dollars will be given ________ can find the lost child.
The climbers _____ their ambition by reaching the summit of the mountain.
I remember her face but I cannot _____ where I met her.
He has left his book here on _____, so that you can read it.
He has left his book here on _____, so that you can read it.汇
The magician picked several persons from the audience and asked them to help him with the performance.