— Mr White has been working all the morning with no rest.— He is a(n) ________ man. He never looks tired.
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.
_______ the rain falling so hard, it becomes more and more difficult to carry on the rescue work.