We must______ using plastic bags in order to protect our earth..
I hate people _________don’t help others when they are in trouble.
—The sweater is very nice. I’ll take it.—But you’d better ________ first. I think it is a little large for you.
– Must I get up early tomorrow morning? – No, _________.
—Mary, could you tell me if your mother ________ our school sports meeting tomorrow? —I think she will come to school if she _________ free.
–Shall we go and ________ hello to the foreign teachers?–Good idea! Let’s go.