Find the underlined part that needs correction in each of the following questions.

13. Mr. Pike’s students didn’t finished all the exercises he gave them last week.

            A. Mr. Pike's   B. finished      C. the exercises           D. gave

14. Whales are one of the biggest animal in the world.

            A. are              B. of                C. animal                     D. in

15. William Shakespeare get married when he was 18 years old to Anne Hathaway, who was 26 years old, and they had three children.

            A. get married             B. was             C. to                D. had 

16. Harry didn't understood what the teacher said in the last lesson.

    A. didn't                             B. understood C. said             D. lesson