had had done表示的意思是在過去的某一時(shí)間之前某事已經(jīng)被做。此為過去完成時(shí)，在這里第一個(gè)had是指時(shí)態(tài)：had done過去完成時(shí)；第二個(gè)had是使役動(dòng)詞：had sth done，讓某事被做。例如：My sister had had the computer repaired.我的姐姐已經(jīng)把這個(gè)電腦修好了。

過去完成時(shí)(had done)

①表示在過去的某個(gè)時(shí)間或動(dòng)作以前已經(jīng)完成的動(dòng)作或已經(jīng)存在的狀態(tài)。就是我們常說的"過去的過去"。

Until then, his family hadn't heard from him for six months.

到那時(shí)為止，他家里已經(jīng)有六個(gè)月沒得到他的消息了。

②表示從過去的過去開始，持續(xù)到過去的動(dòng)作或情況，并且有可能會(huì)繼續(xù)延續(xù)下去。此時(shí)經(jīng)常用延續(xù)性動(dòng)詞。

By the time I left the school, he had taught the class for 3 years.

到我畢業(yè)時(shí),他已經(jīng)教那個(gè)班三年了.

過去完成進(jìn)行時(shí)：had been doing

表示從過去的過去開始，持續(xù)到過去的動(dòng)作或情況，期間一直有規(guī)律的在進(jìn)行、不曾間斷，并且有可能會(huì)繼續(xù)延續(xù)下去。此時(shí)經(jīng)常用延續(xù)性動(dòng)詞。

例：The old clock had been being taken apart of and fixed up again for several times by my 10-year old son before I came back home.

我回到家之前，我10歲大的兒子已經(jīng)把這個(gè)舊鐘表拆卸并重新組裝了好幾回了。

過去將來完成時(shí)：(would have done)

表示到過去將來某一時(shí)間已經(jīng)完成的動(dòng)作，并且對(duì)過去將來那一時(shí)間點(diǎn)產(chǎn)生影響。

例：I believed by the end of that year an advanced version of that software would have been developed, but I was wrong.

我堅(jiān)信到那年年底為止，那個(gè)軟件的新版本將被開發(fā)出來。但是我錯(cuò)了。

表示動(dòng)作從過去某一時(shí)間開始一直延續(xù)到過去將來某一時(shí)間，并且有可能繼續(xù)延續(xù)下去。

例：He told me that by the end of the year he would have lived there for thirty years.

他告訴我，到那年年底為止他將已經(jīng)在那里住了三十年了。