It was the President himself______ opened the door.
We are using ___ of law ______ great effect.
The man needed _____ for one of his legs was badly injured.
I’ll spend the evening ______ in your room waiting for the thief to arrive.
—Car 18 won the race. —Yes. But its driver came close to ______.
. ___ to nuclear radiation, even for a short time may produce variants(变异体)of genes in human bodies.