---I was riding along the street and all of a sudden, a car cut in and knocked me down. ---You can never be careful in the street.
—He failed in the exam again. —He __________his teacher’s advice.
When first to the market, these products enjoy great success.
It is uncertain ______ side effect the medicine will bring about, although about two thousand patients have taken it.
The English in the future will be quite different from the English of today. It is possible that some English words may even ________ completely.
Rainforests __________ and burned at such a speed that they will disappear from the earth in the near future.