题目

求教英语问题
A survey of teachers of Advanced Placement courses in American high schools has found that more than half are concerned that the program's effectiveness is being threatened as districts loosen restrictions on who can take AP courses and as students flock to them to polish their resumes.
1后半段部分的...loosen restrictions on who...
on 是和前面哪个词搭配的?
2末尾处flock to them to 为什么要这样用?

提问时间：2021-03-26

答案

给你分析一下句子结构吧：
as districts loosen restrictions on who can take AP courses
and as students flock to them to polish their resumes.
这两部分是并列关系,用and连接,这里as...相当于when,当什么什么时候
当多地区放松对参加AP课程的限制并且学生们向他们(老师们)蜂拥而至来为自己的简历镀金的时候,这里flock to them to do 就是蜂拥而至做什么什么事情的意思,flock这个词用的很形象.
两个as后面的部分都是从句部分了,实际句子的主干在前面.on 当然是和lossen搭配,loosen on
放松了什么什么政策或东西