If the green light doesn’t come on, you ______ go across the street.
Shen Nong was the first to________tea as a drink.
A lot of food________to that country after the war was over.
Oh,this is really a big shop.Do you know when it________?
—The weather is very good.Let’s go to the seaside. —________.Why not?
We find________impossible for us to learn a foreign language well in a short time.