eager后面加to do不是加doing，be eager to do为固定词组，中文意思是“渴望做某事”。eager词性是形容词，但是在翻译中文习惯中，可以把它翻译成动词。
eager to do造句
1、Some Frenchmen are eager to do that..
2、Be specially eager to do or achieve sth
3、Those who are eager to do so must not share their troubles.
4、Mr Singh, born before partition in territory that is now Pakistan, is personally eager to do so though others in his government, and hawkish opposition parties, disagree.
5、They were eager to do the things first-time tourists do - sail past the Statue of Liberty, stand atop the Empire State Building and stroll through the Metropolitan Museum of Art.
6、Who gave himself for us to redeem us from all wickedness and to purify for himself a people that are his very own, eager to do what is good.
eager的用法与搭配
eager的用法与搭配：eager的意思是“热切的”“渴望的”，指对成功的期望或进取的热情，含有热切得难以等待或难以抑制的意味。eager在句中可用作定语或表语。eager的比较级、最高级有eagerer，eagerest和more eager，most eager两种形式。
1、be eager也可以接动词不定式，表示“渴望做什么”，也可接由介词for所引出的逻辑主语。be too eager to-v的意义不是否定的，而是肯定的。
2、be eager常与介词for，about，after连用，而不与of连用，也可跟that引导的从句，属于较正式的用法。从句中的谓语动词一般为虚拟式。be eager也可以接动词不定式，表示“渴望做什么”，也可接由介词for所引出的逻辑主语。be too eager to-v的'意义不是否定的，而是肯定的。
3、eager表示渴望得到某物，后接介词for，after，about等。如：We are all eager for[after]knowledge.我们都求知心切。表示渴望做某事，后接不定式。如：He is eager to go abroad.他渴望出国。有时可后接that从句，此时从句谓语一般都用'should+动词原形”这样的虚拟语气。