---Is there anything wrong, Bob? You look sad.---Oh, nothing much.In fact, I ____ of my friends back home.
Tell your brother to come _____, because it's going to rain in a minute or two.
A successful scientist needs _____ if he wants to make hypothesis (假设) of how processes work and how events take place.
This year the farmers were just able to gather in the _____ before the fine weather came to an end.
He hated the war so much that he decided to leave the army _____.
We suddenly saw the bus about to leave and had to run _____ to catch it.