____(seat)at the back of the lecture hall,

问题描述:

____(seat)at the back of the lecture hall,
he listened to the professor carefully.
正确答案是Seated,为什么不是Seating?主语不是人吗,不应该用主动式吗?

seat 用作动词,是 使...坐下
所以 he 显然是 被(使坐下),当然要被动