71. If the factory _________ dumping poison into the lake, all the fish and other aquatic animals will die.
A. continues          B. continued                    C. will continue               D. continue
72. You will recognize Jenny when you see her. She __________ a red hat.
A. wears                B. is wearing                    C. will wear                     D. will be wearing
73. Robots save workers from_________dangerous tasks.
A. making              B. having               C. performing                  D. carrying
74. Many people believe that robots have made workers jobless,______that is not necessarily true.
A. but                              B. and                              C. so                                D. or
75. Recent__________developments have made robots more user-friendly and intelligent.
A. science              B. scientist             C. scientific                      D. scientifically
76. Teenagers spend most of their time playing computer games,__________they lost their interests in daily activities.   
 A. moreover         B. so                      C. however                      D. as a result
  77. If we use water __________ , more people will have cleaner water.
A. care                             B. carefully            C. careless              D. carelessly
  78. Water pollution make some aquatic animals_________
A. dying                B. to die                 C. die                     D. died
  79. The team’s success was large __________ to her effort.
A. because             B. due                    C. since        D. because of
  80. English is an__________  language in Singapore.
A. office                B. official     C. officer               D. officially