31. 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

32. You will recognize Jenny when you see her. She _______ a red hat.

A. wears                  B. is wearing                           C. will wear                D. will be wearing

33.  The farmer rides the buffalo -____________ carts loaded full of rice home.

A. draw                   B.  drawing                             C. drew                       D. drawn

34. Little Pascal ____a mechanical calculator which could do additions or subtractions very quickly.

A. discovered          B. found                                  C. found out                D. invented

35. Robots save workers from _____dangerous tasks.

A. making                B. having                                 C. performing              D. carrying

36. Many people believe that robots have made workers jobless______that is not necessarily true.

A. but                      B. and                                     C. so                            D. or

37. Recent __________developments have made robots more user-friendly and intelligent.

A. science                B. scientist                              C. scientific                 D. scientifically

38. 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