将下列句子改为被动式
问题描述：
将下列句子改为被动式
Someone saw him enter the teachers' office.
He was ___ ___ enter the teachers' office.
We heard her singsing a song at that moment.
She ___ ___ ___ ___ a song at that moment.
根据汉语意思完成下列句子：
在英国我有机会与人用英语交流.
In England I'll have a chance to ____ ___ people in English.
答
seen to
was heard to sing
communicate/talk with
/的意思是或者