刚才看见老师进了教室 英语 怎么说

Question

the teacher was seen _ _ into the classroom just now.

Answer 1

Just now I saw the teacher enter（go into） the classroom。

Answer 2

to go

Answer 3

going

Answer 4

填 to go。
这是个被动语态嘛。

Answer 5

walking

Answer 6

填to go
see sb do sth 看见某人做某事 I saw the teacher go into the classroom.
变成被动语态时就成了The teacher was seen to go into the classroom.
see后的不定式作宾语补语不带to 变成被动语态时宾补变成了主语的补足语不定式就要有to