回複：繼續請教，謝在先

不想請假太長失去工作，孩子可以免去回廣州麵試，等父母來美國後，在美國境內由工作簽證轉為綠卡？
-Technically, yes. But the problem is that if the child choose to file I-485 after the parent enters US, the immigration visa application is considered to be abandoned. Thus, if the child is > 21 years old, he/she can not file I-485 and can not apply for the immigration visa either as the parent's derivative due to the age-out problem.

The child can apply for the immigration now is because his/her CSPA age was frozen when he/she filed the immigration visa application,  and if he/she give up this visa application at this time, his/her CSPA age need to be recounted and thus, it may be > 21 years.