题目选项分析

A recently published report indicates that the salaries of teachers continue to lag far behind other college-educated professionals, because they make an average of nearly ,000 a year less at the start of their careers and almost ,000 less a year by the time they reach the age of 50.

A recently published report indicates that the salaries of teachers continue to lag far behind those of other college-educated professionals--by an average of nearly ,000 a year at the start of their careers, and by almost ,000 a year by the time they reach the age of 50.