____( be ) not only the students but also their teacher required to attend the meeting.考察主谓一致,填 is 还是 are?并说明.答案是Are,为啥呢

问题描述:

____( be ) not only the students but also their teacher required to attend the meeting.
考察主谓一致,填 is 还是 are?并说明.
答案是Are,为啥呢