Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Air pollution is getting __________ serious in big cities in the world.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

 If he hadn't wasted too much time, he __________ in his examination.   

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Up to now, they have not made a __________ whether they will go or not.

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

A number of tourists is going to return the evaluation form distributed by the travel agent.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Sarah and I __________ reserved the rooms in the same hotel. She was really surprised to see me there.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

There are many __________ history books in our library.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

We should avoid __________ personal questions.

Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions.