—I saw you come to school by bus this morning.—Oh, I _______ come to school by bus, but it is raining today.
–How long has Robert ________? --Since 2004.
--Why do you want to stay at home? --Because I ________ good when I am with my family.
______ is dangerous for children to swim in the river alone.
Be more careful and we can ______ these accidents.
The mother did all kinds of things to make her baby ______.