56. - Shall we go to the "Travelling in the future" exhibition? - ________________ 56….

A. Great idea! Let's go.                                  B. Not really.

C. Not too bad. And you?                              D. See you then.

57. - What's on the television tonight? -_________________                                       57….

A. I will go to the cinema.                              B. At half past nine.

C. The film is good.                                        D. A football match after the news.

58. Remember to __________ the light before going to bed.                               58….

A. turn on                      B. stop                 C. turn                  D. turn off

59. We are looking for cheap, clean and ................ sources of energy.                          59….

 A. serious                      B. dangerous       C. effective                     D. efficient

60. By the middle of the 21st century, people in developing countries .................          60….

 more renewable energy.

 A. used                         B. have used         C. uses                 D. will be using