II. Supply the correct form of the words in bracket.
1. Unfortunately. Biogas isn’t totally ___________ to people. (harm)
2. Nuclear power is ____________, but it is very dangerous. (plenty)
3. Disposable batteries are _____________ the environment. (pollute)
4. Scientists are finding an _____________ source to replace gasoline. (limit)
5. Will ______________ energy sources be banned from using in the future? (new)
6. We should think ____________ how to protect our environment. (positive)
7. _____________ gas is going to run out someday. (nature)
8. It is predicted that there will be a serious _____________ of energy in the future. (short)
9. Renewable energy is an __________ source of energy. It is unlimited. (exhaust)
10. One of the ______________ of wind power is that it is unavailable. (advantage)
1unharmful
2plenty
3polluting
4limitation
5unrenewable
6positively
7natural
8shorten
9exhaustion
10disadvantage
