【C12】A．destroyB．createC．maintainD．reduce

【C2】______A．hasB．consistC．maintainD．is made up

【C2】A．measureB．keepC．maintainD．grade

Dumped waste might contaminate water supplies.A．destroyB．decreaseC．delayD．pollute

Dumped waste might contaminate water supplies.A．destroyB．decreaseC．delayD．pollute

【C19】A．destroyB．ruinC．damageD．deteriorate

【C8】A．destroyB．disturbC．mistakeD．misuse