Tom and Mike ______ good friends. A is B.am C.不用填 D.are
— _____ Dasan is from Canada, he can speak Chinese very well.— I know he studies Chinese hard.
My sister is only two years old, and I have to _____ her on Sunday.
—What are you doing for your vacation?—________________________.
—I’m tired and stressed out.—You should ___________.
—_________is very interesting to swim in the river in summer,but it’s dangerous.