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44. Is it _____________ to improve our speaking skill?
A. import                                 B. importing                C. importance D. important
45.  The window needs _____________ today to prepare for our party.
A. clean                                   B. to clean                   C. cleaning                  D. cleaned
46. Before I was born, my father had _____________ a teacher.
A. be                                       B. been                        C. being                       D. was
47. They are _____________ a team with two foreign friends.
A. on                                       B. at                            C. in                            D. of
48. Have they ever visited English _____________ countries?
A. speaking                             B. spoken                    C. speak                      D. speaks
49. I _____________ visit my grandmother on Sunday if I don't go to school.
A. would                                 B. wouldn't                 C. will             D. will not
50. _____________ is the most common disaster in Vietnam?
A. What                                  B. When                      C. Where                     D. Which