He made the suggestion that we _____ by train.
—Have you got an i Phone 5?—No.—You' d better buy ____.It' s really cool!
—When I first got to Harvard, my awkward English brought me great trouble.——Oh, dear, it _______a struggle for you to keep up with other students.
—Jack, did you see my son Harry just now?—No,Mrs. White. I _______computer games.
Water, which seems so simple and common, is ______ makes life possible.
—Jimmy had a lot of parties recently.—Yes, that might ______ why he didn't do well in the test.