41. By the end of next March, I _______ English for five years.      A. had been studied                                            B. had been studying      C. will have been studying                                 D. will have studied 42. Linda took great photos of butterflies while she _______ in the forest.      A. was hiking                B. is hiking                    C. hiked                        D. had hiked 43. When I _______ for my sister in front of the supermarket, a strange man came to talk with me.      A. was waiting              B. waited                       C. had waited                D. were waiting 44. When I came to visit her last night, she _______ a bath.      A. is having                   B. was having               C. has had                     D. had had 45. John _______ in the same house since he left school.      A. lived                         B. had lived                   C. was living                 D. has lived 46. He will take the dog out for a walk as soon as he _______ dinner.      A. finish                        B. has finished              C. will finish                 D. finished 47. The phone _______ suddenly while Joanna was doing the housework.      A. rang                          B. was ringing               C. had rung                   D. is ringing 48. A fire-fighter was injuried severely while he _______ to put out a fire.      A. would help               B. helped                       C. has helped                D. was helping 49. By the time I came here all the better jobs _______ taken.      A. have been                 B. were                         C. are                            D. had been 50. While Peter _______ the rose bush in the back yard, the phone rang.      A. had been watering    B. watering                   C. watered                     D. was watering