Things are ________ on Mars ________ on Earth because of the different gravity.
----How about having a picnic next weekend? ---- It _____great.
Lucy is ill.She has a bad cold for several days.
Yougo and ask Tom.Heknow the answer.
—I put the bike here? —No,you can’t.
—Who is knocking at the door? —It be Miss Zhang.Because she has just gone to Japan.