It was the president's speech that the secretary spent the whole morning at home.
A. to prepare
B. preparing
C. prepared
D. be prepared
网友回答
A. to prepare
(答案→)B. preparing
C. prepared
D. be prepared
解析：本题中含有一个强调句型，强调的是句子的宾语preparing the president's speech；在英语中，通常动名词可以在句中做宾语。本句中是一个固定搭配spend some time in doing stt花费时间做某事；句义：秘书花了整个晚上在家里准备的正是总统的演讲。故B正确。