Supply the correct passive form of the verbs in brackets.

      1.   This computer                                   (use) for two years.

      2.   America                                 (discover) by Christopher Columbus.

      3.   I think this institution                                              (widen) twice since 1999.

      4.   Sydney Opera House in Australia                         (finish) in 1973.

      5.   My sister is studying law at Viet Nam National University, Ho Chi Minh city now. This university                              (situate) in Thu Due District.

      6.   The Great Wall in China                             (build) many centuries ago.

      7.   David and his father                                    (visit) the Temple of Literature last week.

      8.   The Golden Gate Bridge in San Francisco                                   (complete) in 1937.

      9.   The University of Cambridge                                 (form) in 1209. It is always considered to be one of the most prestigious universities in the world.

      10. BurjKhalifa in Dubai, the highest building in the world,                                  (open)in 2010.