有个小问题，英语答疑网上看到一个句子：
So over time, we took hundreds of thousands of people out of the pool of those who might want a gas station attendant job and pushed them up, toward the professional job market, adding a lot of value to society and their wallets.
toward the professional job market前后都有逗号，但这个短语仿佛不是做解释之类的，为什么toward前为什么要加逗号，是做并列？toward那个逗号能否去掉，谢谢老师。
逗号，在语言中有哪些用途，有时要紧，有时并无关紧要。它在不少状况下表示停顿：一个“意群”的停顿，体现语言表达的“抑扬顿挫”。比如：
pushed them up, toward the professional job market,adding a lot of value to society and their wallets.——这里面就有3个“意群”，两次停顿：
1. push sb. up：把某人推上。（谓语）
2. toward the professional job market：朝着专业人才就业市场。（这个词组用来表示pushed them up的方向）
3. adding a lot of value to society and their wallets：有益于社会，有益于个人收入。（目前分词表示结果。）
最后说一下，那个逗号可以省略。有逗号也不可以并列，缺少连词and。