He is very sorry _____ that.
—Excuse me, ____ is the post office? —About 500 meters away.
—Where ____ you ____ lunch? —At home.There was no school lunch
I’m not sure about the meaning of the word. You’d better look it up in a ____ .
Trees ____ fight air pollution.They are natural air conditioners.
____ it snowed heavily yesterday, nobody in our class missed the lesson.