Every student as well as some teachers who ___ to take care of the students ___ asked to be at..

这句话的主干是：Every student is asked to be at the school gate before 6 in the morning.
Every后面跟is.
Some teachers who are to take care of the students是student的同位语，teachers是复数，跟are.
中文翻译应是：每位学生以及负责这些学生的老师都要求在早上6点以前到校门口。

who后面引导的句子指teachers
所以是复数
every student is asked to be
是单数
中间的as well as some teachers who are to take care of the students是修饰student的
意思是和这些照顾学生的老师们一样

了解"as well as"是强调其前面的主语的,
所以主要是描述"Every student"的,再把握整体结构:
Every student is asked to be at the school gate before 6 in the morning .
而
who are to take care of the students 这是修饰"teachers".

除了一些照顾学生的老师外,每个学生都被询问了关于...

这道题应该选a．who ___ to take care of the students 是定语从句修饰some teachers，who指代的就是some teachers，所以用are．
第二个空格的主语是Every student as well as some teachers ，as well as 遵循就前原则，所以用is．
这句话的意思是每一位学生和一些照顾学生的老师都必须在上午六点之前在校门口集中．

第一个选are因为它跟着的who修饰的是teachers，复数。后面选is因为它是Every student的谓语，单数，其实这句句子还可以这