Most whales must come up for air after several minutes, _______ a few can stay under water for an hour or more.
There is a peaceful and calm ________ in the country, quite different from that of a big city.
---Where did you ________ our chemistry teacher? --- It was in the supermarket ________ I bought the moon cakes.
John is the only one of the students in our class that never ________ a mistake even when it is pointed out to him.
Only after leaving home ________ the true meaning of the proverb, “East or west, home is best.”
--- Why do you suggest Mount Lu? --- I believe________ beauty of nature there will make________ excellent impression on you.