这句中的“far more than they used to” 是副词短语 在这里做状语 修饰谓语worry about real or imagined dangers
原句=parents worry about real or imagined dangers far more than they used to （do)
这句中的“far more than they used to” 是副词短语 在这里做状语 修饰谓语worry about real or imagined dangers
原句=parents worry about real or imagined dangers far more than they used to （do)