Sara Nir was up late, checking her email when she heard knocking sounds that went from a soft tapping to hard pounding to a frightful crash overhead -- as if a wall had collapsed in the unit above her ground-floor condo. 


원문출처 : https://www.cnn.com/2021/07/03/us/surfside-condo-collapse-questions-unanswered-invs/index.html