---What do you think of your teachers? ---Sometimes they are too strict __________ us _________ our study.
—Is ______ here? ---No, Tom isn’t here. But it’s time to have class.
He turned around, but he couldn't see_______.
Yesterday I saw Amy ____________.
It is terrible. The cat miaowed a lot at night recently. It _________ a baby crying.
In spring, it is good for you to sleep ________your windows open.