现在完成进行时可以表示动作的重复，而现在完成时一般不表示重复性。
你最近常和他见面吗？Have you been meeting him recently ？
你最近见到过他吗？Have you met him recently ？
现在完成进行时有时含有感情色彩，而现在完成时一般是平铺直叙。
我一直等了你两个小时。（可能表示不满）I have been waiting for you for two hours
我等了你两个小时。（说明一个事实）I have waited for you for two hours
现在完成进行时强调动作，而现在完成时强调结果。
谁一直在吃这些桔子呀？（还剩余一些）Who has been eating the oranges ？
谁把桔子吃光了？（强调吃得一个不剩）Who has eaten the oranges ？
过去完成进行时是由“ had been +现在分词”构成。
她在考试之前一直患重感冒。She had been suffering from a bad cold when she took the exam
这对情侣已经同居了十六年。 The couple had been living together for 16 years
他们期待这个消息有一段时间了吧？Had they been expecting the news for some time?
尽管拉斐尔没做什么错事，但他还是挨骂了。Rafael was scolded even though he hadn't been doing anything wrong
过去完成进行时表示动作在过去某一时间之前开始，一直延续到这一过去时间。和过去完成时一样，过去完成进行时也必须以过去时间为前提。
这东西我找了好多天才找着的。I had been looking for it for days before I found it
他们只等了一会儿车就来了。They had only been waiting for the bus a few moments when it came
表示反复的动作
他过去多次向我提到过你的名字。He had been mentioning your name to me
你对我真是有求必应。You had been giving me everything
过去完成进行时还常用于间接引语中
医生问他吃了什么。The doctor asked what he had been eating
我问他们那些天是待在哪儿的。I asked where they had been staying all those days
过去完成进行时之后也可接具有“突然”之意的 when 分句
我刚看了几分钟他就进来了。I had only been reading a few minutes when he came in
她温习功课才一会儿，她妹妹就打断她了。She'd only been reviewing her lessons for a short while when her little sister interrupted her
她已经打扫过办公室了，所以很整洁。She had cleaned the office so it was very tidy
她一直在打扫办公室，所以我们不得不在外面等着。She had been cleaning the office so we had to wait outside
nothing but, no +名词 but, 只有；仅仅
nothing but, no +名词 but, but 等于 only ，表示肯定意义，后接名词、代词、不定式等。
在我们班上，只有他能游过这条河。No one but him in our class can swim across the river
她只好在这时等，别无他法。She could do nothing but wait here
not without, 没有就没有在这个句型中，使用两个否定，用来加强语气，表示肯定意义。
没有空气，人们甚至连几分钟也不能生存。One cannot live even a few minutes without air
有你们的帮助，他们才按时完成了任务。They couldn't have completed their task on time without your help
too not to, 和 never too to, not too to, 这类双重否定的句型，也表示肯定意义。
这个男孩很聪明，不会解不出这道数学题。The boy is too clever not to work out this maths problem
改过不嫌晚。It is never too late to mend
你永远不会大到再也不需要学习了。You are never too big to stop learning
让你刷自己的鞋，这要求并不过分。It's not too much to ask of you to clean your own shoes
not until, 直到才 until 可作介词，也可作连词。作介词时，后接名词、代词或短语；作连词时，后接句子。 not 后面接非延续性动词。
直到车上坐满了乘客，汽车才开走。The bus didn't leave until all the seats were taken
not until, 也可用于强调句型和倒装句式中。
直到今天上午，他才完成那项工作。it was not until this morning that he finished the work
hardly when, scarcely when, 一（刚）就 when, 是并列连词，其前面的句子要用过去完成时，其后的句子用一般过去时。
他一到天就开始下雨了。He had hardly arrived when it began to rain
He had scarcely arrived when it began to rain
一（刚）就no sooner than
在这个结构中， no sooner 位于主句中，主句用过去完成时， than 引导状语从句，从句用一般过去时。
他们刚跨进剧院，音乐会就开始了。No sooner had they got to the theatre than the concert began