50. A. getting         B. gets                    C. to get                  D. got

A

Up to now, I have been teaching here for more than ten years. When my students see me, they would wave to me and say hello. Maybe you think that is the same to every teacher, for the students are taught to respect their teachers. It is true, but there is something different here. They like me because we are on good terms, just like close friends and they often say “Tom, you are really something. How can you be so successful and energetic（有活力的）all the time?” At this time, I would smile at them and say “I am flattered（奉承）. One point I like to mention is that you should learn how to be friends with people around you. That is to say ‘Don’t step on other’s toes’.  By and by, you will probably find that more and more people would be happy to help you when you are in need. Of course, you have to be knowledgeable and capable（有能力的）as well. Then one day, when the opportunity comes, you can make great success.”  

     49. A. difference    B. differently           C. different             D. difficulty

     48. A. changed       B. changed              C. has changed         D. is changing

     47. A. mean           B. meant                 C. means                 D. meaning

     46. A. hard            B. easily                  C. easy                    D. hardly

     45. A. in                B. to                       C. on                      D. of

     44. A. difference    B. difficult              C. different             D. difficulty

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

     42. A. look at         B. look out              C. look up               D. look for

     41. A. put              B. to put                 C. put                     D. putting