bài 1:.The wind, the sun, and the wave are some types of sources of ___________ energy.

A.changeable     B. renewable    C. cheap   D. costly

Bài 2: 1 Nuclear power is expensive and dangerous ___________ our environment.

A.for   B. to   C. in    D. of

bài 3: 1 Low energy light bulbs should be used to ___________ electricity.

A.spend    B. buy    C. convert    D. save

bài 4: 1 ___________ energy is produced by collecting sunlight and converting it into electricity.

A.Hydro   B. Nuclear    C. Solar    D. Wind

bài 5:Human is looking for a clean, cheap and ___________ sources of energy.

A.effective    B. effect    C. effectively      D. effectiveness

Bài 6: 1 My kids ___________ downstairs now. They ___________ chess.

A.am/am playing        B. is/is playing            C. are/are playing       D. be/being