问题
单项选择题
The professor is quite difficult pleased.
A．to please
B．to be pleased
C．for pleasing
D．pleasing
答案
参考答案：A
解析：[分析] 结构应用。 此句是用动词不定式作主语：To please the professor is difficult．此句常写作：It is difficult to please the professor．因此答案为A。