Ⅱ. Complete the passage with proper words or the correct forms of the words given.
Wind energy is one of the most important

1. (nature) resources in the world. It is clean and renewable. This means it will never run out. Many people want to know 2. wind energy can be turned into electricity. In fact, wind power plants are built in places with strong winds. The wind blows the large blades* of the wind turbines, and then electricity 3. (produce) through a series of processes.
Compared with fossil fuels*, wind energy causes no pollution. It helps reduce the air pollution caused by burning coal or oil. Also, wind turbines work
4. (quiet) and don't take up too much space. That's why more and more people are 5. (crazy) about it. Now, countries 6. (develop) wind energy.
In some areas, wind power even provides enough electricity for thousands of
7. (family). However, wind energy also has some limitations. For example, it depends on the weather. There will be no electricity if there is no wind at all. Scientists are trying their best 8. (solve) this problem. They hope 9. wind energy can become the main energy source for humans in the future.
As students, we should learn more about clean energy like wind power. It's our duty to protect the environment, and using clean energy is 10. good way to start.

Ⅱ. 1. natural 2. if/whether/how 3. is produced 4. quietly 5. crazy 6. are developing 7. families 8. to solve
9. that 10. a