WORD FORM
1.Some __________ groups have worked effectively ( environment )
2.Polluted water can __________ do harmful to people's health ( direct )
3.A___________ faucet can waste about 500 liters of water a month ( drip )
4. ___________ energy is an effective,clean and cheap source of power ( sun )
5.I am extremely __________ about my next exam ( worry )