(七)不定式的时态。动词不定式一般有三种时态形式，即一般式、进行式和完成式。
　　(1) 一般式(to+动词原形)：表示与主句谓语动词动作同时(或几乎同时)发生或在主句谓语动词之后发生的事情。例如：
　　We’re happy to have you on our side. 有你在我们这边我们很高兴。
　　I saw him go out. 我看见他出去了。( 不定式go out 与 see同时发生。)
　　They invited me to have dinner with them.  他们邀请我和他们一起吃晚饭。
　　I hope to see you again. 我希望再见到你(to see发生在hope之后)
　　(2) 进行式(to be+现在分词)：表示主句谓语的动作发生时，不定式动作正在进行。例如：
　　She’s said /believed to be living nearby. 据说/据信她就住在附近。
　　When he came in, I happened to be sleeping in bed. 他进来时，我碰巧正在床上睡觉。
　　They seem/appear to be enjoying themselves. 看上去他们似乎很快活。
　　He pretended to be doing his homework when he heard his father’s sound. 他听见父亲的声音，假装正在做作业。
　　The president was reported to be visiting the hospital. 据报道总统正在访问那家医院。
　　(3)完成式(to have+过去分词)：表示在主句谓语的动作之前发生的事情。
　　如：I’m glad to have met your parents here. 我很高兴在这儿见到了你父母。(已见过)
　　I’m sorry to have kept him waiting for me so long. 我很抱歉让他等了我这样久。(已经等过了)
　　动词不定式的完成式和下列动词的过去时连用，表示过去没有实现的事情：plan, hope, expect, be, intend, mean, wish, 等。注意一定是它们的过去时。另外还有should/would like/love。这个结构表示“本打算/想/计划…”的意思。例如：
　　The game were to have taken place in Room. 比赛原计划在罗马举行。
　　He planned to have gone abroad last week.= He planned to go abroad but he didn’t. 他原计划上周出国的。
　　I’d like to have been offered the job and(to have been)given the opportunity to prove myself. 我真想(当时)把这个工作给了我，给我个机会让我证明我自己。
　　同样的意思也可用上述动词的过去完成时加动词不定式的一般式来表达。例如：
　　I had hoped to visit the great pyramid .= I hoped to have visited the great pyramid.=I hoped to visit it, but I didn’t. 我本希望参观大金字塔的。
　　They would have liked to have your help.=They would like to have had your help.=They wanted to have your help but they didn’t have it. 他们本想得到你帮助的。
　　(八)不定式的被动语态。当不定式的逻辑主语是这个不定式所表示的动作的承受者时，不定式一般要用被动形式。不定式的被动形式有两种：
　　一般式：to be+过去分词
　　完成式：to have been+过去分词
　　例如：
　　You’re lucky to have been accepted . 你很幸运已经被接受了。
　　These criminals are to be hanged .  这些罪犯是将被绞死的。
　　We’re glad to have been invited.   受到邀请我们很高兴。
　　What’s to be done next? 下一步做什么?
　　It is an honor for me to be asked to speak here.   我很荣幸应邀在这里讲话。