--- ________ David be the new chairperson of the Students’ Union?--- He _______ be, but I’m not sure.
Miss Gao asked a question, but it was ___________that nobody could answer it.
John called me as soon as he _______ my package.
This room is _________for you to live in.
—Do you walk to school every day? —I used to walk, but now I ride to school _______ walking.
______ careful you are, ______mistakes you will make.