--- You needn't take an umbrella. It isn't going to rain.
--- Well, I don't know. Itdo.
Every possible means ______ to prevent the air pollution, but the sky is still not clear.
My father and my mother have been married for 30 years, and never once ______ with each other.
Although the old man was ______ death, he still fought with the disease bravely.
Many countries are increasing their use of natural gas, wind and other forms of ______.
It may not be a great suggestion. But before ______ is put forward, we will make do with it..