Question 5. While the two thieves ______, someone stole their car.

1. argued B. are arguing C. were arguing D. would argue

Question 6. We should use paper and other materials as ______ as we can.

1. economy B. economic C. economised D. economically 

Question 7. Once ______ environmental damage is done, it takes many years for the system to recover.

1. the B. a C. an D.

Question 8. I wish we ______ three months for summer holiday, as in my grandparents' time.

1. have B. had C. will have D. can have

Question 9. Many ethnic minority groups find it hard to ______ their own languages.

1. protect B. maintain C. guard D. defend

Question 10. The secretary to ______ I talked didn't know where the meeting room was.

1. whom B. who C. that D. which

Question 11. None of the servants were ______ when Mr. Smith wanted to send a message.

1. available B. attainable C. approachable D. applicable