问题

To their disappointment, they found the lecture given by the professor difficult__________.

A:to be understood
B:to understand
C:understanding
D:understood;

正确答案是：

同类题型

No dictionary can ______all theEnglish idioms

_____ she got a dictionary

We arrived _______the farm ______ a Tuesday morning .

We like Mr Wu because he sometimes _________ us interesting stories in his class.

Why were you so late for work today— ____ to the office was not very easy thismorning because of the traffic