书名：怪物讲师 阅读
页数：p.127
题目：
I ______ that the application form for the mortgage loan was recieved and fina
l decision will be made soon.
A. assure
B. have assured
C. was assured
D. was assuring
疑问：
为什么答案是C不是B,不太能理解为什么需要使用被动式
谢谢