______ the red switch on the left and the flying machine will swiftly go up into the air and _____ its journey.
---Would you like some more beef? ---No, thanks. I’m ______ a diet.
At the wedding, he sang a song specially written for the ____.
----- Is that Mr.Smith over there? ----- No, it _____ be him --- I am sure he is much taller.
---Is it good to look up every new word when I come across it in reading? ---No. You ______because you are likely to guess the meaning from the context. A. can’tB. mustn’tC. don’t have to C. ought not to
—Shall we go out for meal this evening? —Yes,that’s good idea.