30.3-ENGLISH 7(4)

Convert st into st nghĩa là gì

come from

Alternative source of energy nghĩa là gì

biogas nghĩa là gì

root ?

concentrate on

do research on st

_________ energy sources can be used to create energy, generate electricity, or drive big machinery but they are harmfulto the environmen

• A. Solar

• B. Non- renewable

• C. Wind

• D. Renewable

The sun and the wind are other _________ sources of energy

• A. alternative

• B. limited

• C. harmful

• D. polluted

7. A non- renewable source of energy can be used to power machinery, but it also _________the environment.

• A. cleans

• B. pollutes

• C. helps

• D. protects