Guess, how much does it cost? —I think it costs15 and 20 dollars. [ ]

Have you ever been to Shanghai, Mary?—Yes. I ______ there for three days with my parents last year.

Man landed ______ the moon in 1969 ______ the first time. [ ]

Which city would you like to______? —Fujian. I______ there twice.

Can he work out the maths problem? —-I think _____ hard for him to work it out.