Nam was playing football, _    ?

With above 20,000 species, the world’s population of ants has continued to increase even as other animal populations have declined.

The medical problems of parents and their children tend to be very similar to because of the hereditary nature of many diseases.

If everyone _________, how would we control air traffic? Surely, we'd all be crashing into each other. 

The office …………on the weekend.

It is believed that the more frequent you exercise, the greater physical endurance you will have

If we hadn’t got lost, we ____arrived much earlier. 

Some birds can travel at speeds approaching one hundred miles an hour, and a few land animals can so.

One of the four underlined parts marked A, B, C, D in each sentence is not correct in standard English. Identify them: 

If drivers obeyed the speed limit, fewer accidents occur. 

When I walked into my office, I found Tom was using my telephone

Had we known the traffic would be so bad, we did not drive back from work so early.

The first vaccine ever developed was used to combat and fight a smallpox, a disease resulting from infection by a virus.

It is large island, few people live there, though.

The most of the energy used in our homes and factories is generated from coal, oil and natural gas

The Library of Congress, located in the nation’s capital, houses history documents and photographs as well as most books published.

They met him at the party last night, _    ?

It’s a lovely old house, I agree, but can we afford to moderning it?

Choose the correct answer to complete the sentence. "With clear evidence, his company couldn't deny having _____ a large quantity of toxins into the sea."

The society was set up to ...... endangered species from extinction.

Approximately 80 percent of farm income In Utah are derived from livestock products

Louie played.......... basketball and.......... baseball at ..........Boy’s Club this year.