One World Trade Center a. ___________ (to become) New York's tallest building, overtaking the Empire State Building, after a steel column was lifted into place.
The World Trade Center project b. ____________ (to suffer) several delays over designs and naming.
The building, construction of which c._______________ (to begin) in April 2006, will be 1,776ft tall when completed.
The World Trade Center's twin towers were destroyed on 11 September 2001.
The skyscraper, dubbed Freedom Tower, d.__________(to become) the tallest building in New York a day before the one-year anniversary of the operation that killed Osama Bin Laden.
Answers: a. has become; b. has suffered; began; c. became