Another driver had just driven into the back of Jack's car ______ he was waiting at some traffic lights.
The old man's ______ pity on the snake led to his own death.
It is no good ______ today's work for tomorrow.
It's no use______ with him. You might as well ______ with a stone wall.
I couldn't understand ______ at the poor child.
We can't understand ______ a decision until it is too late.