---- What do you think of haze(雾霾)? ---- It ____ us we all must try to do something to stop the air pollution.
Bob is a good boy at school. He _____ fights with others.
—Either Laura _____ Amy _____ American. —Amy is.
— _____ does he live from our school? — About thirty minutes’ walk.
Tom usually gets up _____ half past six _____ Saturday morning.
Mr Green is our new teacher this term. He teaches _____ history.