---______plastic bags we use, _____it will be to the environment.----I agree ____you .
-----Is that your book ? ------No, ________ .
It is 8 o’clock now. Tom must _____ to school .
If (如果) you have problems (问题),you can ask Tom _____ help.
Please call Jenny _____ 4687687.
Look at those ________. They are _______