21.—Could you do me a favor to lift these booked to my office Black?

—     ,Mr.Smith.

  A. It's a pleasure                                      B. With pleasure.

C. It. depends                                            D. Why not?

22.I would really appreciate _____if you would like to teach me how to monitor the robots.

  A. that.                   B. this.                       C. it.                        D. you.

23.Education is a lifelong process, _______process that starts long before _______ start of school, which should be a necessary part of  one's  entire life.

  A. a; a                    B. a; the.                    C. the; a                    D. the; the