Mrs O’Neill asked __questions and she didn’t scold us either.
---- Why does the river smell terrible? ---- Because large quantities of water______.
Cathy went to the hospital alone. If she had told me about it, I _____ with her.
Of all the books on the desk, ______ is of any use for study.
Sam _____ some knowledge of the computer just by watching others working on it.
A new iPad in the market costs about ______ of a second-hand one.