difficulty后接in doing sth時，意思是“做某事有困難”，其中的介詞in含有while的意思，表示“當……的時候”“在……的過程中”，整個結構的意思是“當做某事的時候有困難”“在做某事的過程中有困難”。如：
We had difficulty in finding a parking place. 我們費了很大勁才找到一個停車位。
They shouldn’t have any difficulty in finding the house. 他們找這房子時大概不會有困難。
If you should have any difficulty in getting spare parts ring this number. 萬一你買備件時遇到什么困難，請打這個電話號碼。
One way of deciding what to do when you have difficulty in choosing the best course of action is to toss a coin. 當人們遇到困難不知選什么行動方案最好的時候，一個辦法就是扔硬幣來決定干什么好。
注：該結構中的介詞in有時可以省略。如：
I had difficulty carrying out the plan. 我執行這項計劃有困難。
She was having great difficulty getting her car out, and so I had to move my car to let her out. 當時她正無法把車子開出來，所以我就移開了我的車子讓她開出來。
另外，若difficulty后沒有出現動名詞，而是接名詞，則要用with sth。如：
Some people had difficulty with the lecture, but most understood. 有些人聽講有困難，但大部分人聽懂了。
If you have the least difficulty with the arrangements for the conference, phone me at once. 如果你安排會議有什么困難，馬上給我打電話 初三。
二、后接about doing sth
difficulty后接 about doing sth時，表示關于做某事的困難，其中的介詞about意為“關于”。如：
There shouldn’t be any difficulty about getting you a visa. 給你弄個簽證不會有什么困難吧。
注：about后也可直接跟名詞作賓語，此時的about仍表示“關于”的意思。如：
There oughtn’t to have been any difficulty about it 此事本不應有什么困難。
此時還可用介詞over表示類似意思。如：
There doesn’t seem to have been any difficulty over the money question. 在錢的問題上似乎沒發生什么困難。
三、后接of doing sth
difficulty后接of doing sth時，表示做某事的困難，其中介詞of表示所屬關系，相當漢語的“的”字。如：
He tried to explain to me the difficulty of learning to cook from books. 他向我解釋照著書本烹飪的困難。
One of the annoyances of working here is the difficulty of parking near the office. 在這里有一件傷腦筋的事，就是在辦公處附近很難停車。
Both “feat” and “achievement” emphasize the difficulty of accomplishing something mental or physical. feat和achievement均著重指在腦力或體力方面完成某事物的艱巨性。
注：of后也可直接跟名詞作賓語，此時的介詞of仍表示所屬關系，意為“……的困難”。如：
She has no notion of the difficulty of this problem. 她不了解這個問題的難處。
Do you understand the difficulty of my position? 你了解我處境的困難嗎?
本文來自：逍遙右腦記憶 http://www.lg566.com/chuzhong/36166.html
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