— We must act now because time is __________.— Yes. Let’s start.
If you are tired, you can ________ a rest.
The school has eight _______ students.
-----I have to go now. -----It is raining .Don’ t ______ until(直到) the rain stops.
I have a new ______ . I can put my money in it.
Water is very dangerous sometimes. So we must be careful _____ it.