The past few centuries have witnessed balloon's expansion into v

The past few centuries have witnessed balloon's expansion into various aspects of life.While small balloons are used as colorful decorations,scientists use weather balloons to collect meteorological data from the atmosphere. Balloons are even used by doctors to inflate'"the blood vessels of patients to aid in circulation .
【正确答案】：医生甚至用气球来“扩张”病人血管，改善血液循环。（考点：“inflate”的理解与翻译)