Directions: For each of the following unfinished sentences there are four choices marked A, B, C and D. Choose the one answer that best completes the sentence.
21. The air quality in the city, _____ is shown in the report, has improved over the past two months.
A. as B. it C. that D. what
22. The little child stood on the chair to make himself _____ taller.
A. looking B. to look C. looked D. look
23. Born and brought up in the East, I had to get used to the English accent_____ sounded quite different to our way of speaking.
A. who B. where C. which D. when
24. Not only the students but also the teacher in the past three courses from the new teaching method.
A£®have benefited B£®has benefited C£®benefit D£®is benefited