Âm thanh chia sẻ

The Frame of a Skyscraper In the city, they are building a new skyscraper. First, they make a strong foundation. Then, they start putting up the steel frame. A big crane lifts the steel columns. Workers bolt them to the columns below. Then they lift the steel beams. They connect the beams to the columns. Floor by floor, the frame goes up. It looks like a giant metal skeleton. CONVERSATION 3: On the Steel Structure Two construction managers are talking at the bottom of the building.  Manage