会计学2．不定式的进行(jìnxíng)时表示动作与谓语动作同时发生。不定式、分词、动名词的完成式表动作在谓语之前发生。(1)Whenmothercameintotheroom，Sidpretendedtobeworkinghardathislesson.(2)Robertissaidtohavestudiedabroad,butIdon’tknowwhatcountryhestudiedin.(3)Havingfinishedallmyhomework,IwentouttoplayfootballwithLiMing.(4)Theboywasseverelypunishedbyhisfatherforhavingtoldlies.3．不定式做定语时，如果不定式是不及物动词，或者不定式所修饰的名词是不定式动作的工具、地点，不定式后就应有必要的介词。Therearefivepairstochoosefrom，butI'matalosswhichtobuy.4．不定式主动表被动的几种情况(qíngkuàng)：在Therebe结构中，做定语的不定式既可用主动语态也可用被动语态。Thereisalotofworktodo/tobedone.不定式做定语时，如果不定式所修饰的名词是不定式的宾语，但是又可在句子中找到另一个词做不定式的逻辑主语，不定式要用主动语态(yǔtài)。Wouldyoupleasegivetheboysomethingtoread?(something是read的宾语，theboy是read的逻辑主语，不定式用主动语态(yǔtài)。)注意比较下列两个句子：Ihavesomeletterstotype.(Iwilltypethelettersmyself.)Doyouhaveantletterstobetyped,sir?(Iwilltypethelettersforyou.)5．关于不定式的省略在连词than，as后、介词except，but，besides后，如果前有实义动词(dòngcí)do的某种形式，动词(dòngcí)不定式一般不带to，反之则带to。(1)Inthatcase，thereisnothingyoucandothanwait.(2)Helikereadingnovelsbesidestoplaythepiano.使役动词(dòngcí)make,let,have和感官动词(dòngcí)see,watch,hear,observe后接不定式做宾补时要省to，但在被动语态中，to不能省。(1)Acomputerdoesonlywhatthinkingpeoplehaveitdo.(2)Pauldoesn’thavetobemadetolearn.Healwaysworkshard.6．admit，advise，avoid，appreciate，can'thelp，consider，delay，deny，escape，enjoy，finish，feellike,fancy，imagine，mind，miss，practise，risk，suggest等动词以及(yǐjí)所有带介词的短语动词后面只能跟动名词做宾语。(1)Ireallyappreciatehavingtimetorelaxwithyouonthisniceisland.(2)Theboywasluckyenoughtoescapebeingpunished.7．remember，forget，try，mean，regret，stop，goon后接不定式做宾语与接动名词做宾语，意义(yìyì)有很大区别，必须牢记。regretdoing因做过某事而后悔，动作已发生regrettodo因将做某事而遗憾，动作没发生rememberdoing记得做过某事，动作已发生remembertodo记得去做某事，动作没发生forgetdoing忘记曾做过某事，动作已发生forgettodo忘记做某事，动作没发生meandoing意味着meantodo打算做stopdoing停止做……stoptodo停止做某事而做另一件事trydoing尝试(chángshì)做……trytodo努力做(1)Shesearchedthetopofthehillandstoppedtorestonabigrockbythesideofthepath.(2)—Youwerebraveenoughtoraiseobjectionsatthemeeting.—Well,nowIregrethavingdonethat.(3)—Iusuallygotherebytrain.—Whynottryg