Choose from the options A to D, the one which most suitably completes each sentence.

Here are the answers to the questions:

1. Only I am qualified to the contest.

   • The correct option is C. am.

2. If Thomas were our leader, no one would disobey him.

   • This is a conditional sentence (Type 2) expressing an unreal situation. The correct option is D. were.

3. My brother is doing a three-year course at the university.

   • "Three-year" acts as an adjective modifying "course". The correct option is A. three-year.

4. During the interview, all the candidates made signals to one another.

   • "To one another" is used when referring to more than two people. The correct option is D. one to another.

5. It is time we all left for home.

   • The phrase "It is time" is followed by the past simple tense to express that something should have been done already or should be done now. The correct option is A. left.

6. All of us saw the man pick up the bucket.

   • After "saw" (a verb of perception), we use the base form of the verb when the action is completed. The correct option is A. pick.

7. I was too sad to hear of his death.

   • "Too" is used before an adjective to mean "more than enough" or "excessively". The correct option is C. too.

8. The woman refused to sell me any kerosene.

   • "Any" is used in negative sentences. The correct option is D. any.

9. We try always to maintain discipline ---? don't we

   • This is a tag question. The main verb is "try" (positive), so the tag should be negative and use the auxiliary verb "do". The correct option is C. don't we.

10. He spoke little French and so he couldn't help them.

    • "Little" (without "a") means "hardly any" and implies a negative sense. The correct option is D. little.

11. Neither of the two boys wanted to be in the relay team.

    • "Neither" is used to refer to two people or things, meaning "not one and not the other". The correct option is C. Neither.

12. I would like to congratulate you all on your excellent performance in this examination.

    • The verb "congratulate" is followed by the preposition "on" when referring to the reason for congratulation. The correct option is D. on.