21.    — Is this your mother’s car?

        —No. car is blue.

        A. My                                   B. His                                C. Her                               D. Your

22.    The 24^th Winter Olympics will be held in China_________2022.

        A. at                                     B. in                                  C. on                                D. to

23.    There’s no bus to that small village, ____________we have to walk there.

        A. or                                     B. so                                 C. but                               D. for