polluted water can directly do ... to people's health and destroy marine life.

A. harm  B. destruction  C. terror  D. ruin

There are some cracks in the water pipes. Why don't you call a(n) ... to replace the pipes?

A. mechanic  B. electrician  C. plumber  D. butcher

Solar energy can help people ... the earth's resources.

A. protect  B. conserve  C. consume  D. profit

Underline word or phrase that needs correcting and provide correction.

When Vostok 1 was launched in 1961, the dog Laika has already been in Sputnik 1.

Underline word or phrase that needs correcting and provide correction.

The first spacecraft which was successfully launched in 1961 belong to Russia.