13. Complete the text with the correct words.

WATER POWER

One way of exploiting water power is with a dam. Water is stored in a 1. . When the 2. is opened, the water is released through a 3. that spins a 4. , activating a 5. .
Another way is using 6. and tides. Periodic 7. of water are forced through a 8. that active a generator.

14.1 Listen to an environmental engineer talking about the use of tidal power plants and tick the words you hear.

14.2 After listening the track in the previous exercise, complete the following sentences.

1. Sea can give us green energy.
2. The for electricity is ever-growing.
3. At different times during the day, seawater recedes and rises along the .
4. A is a phenomenon caused by the attractive forces of the Moon and the sun.
5. When the pull of the Moon is , water levels fall.
6. When the pull of the Moon is , water levels rise.

15.1 Write a sentence using the word stream. aperta

15.2 Write a sentence using the verb to harness. aperta

15.3 Write a sentence using the word reservoir. aperta

15.4 Write a sentence using the word blades. aperta