英文12時式

我曾經答過~quote多次俾你睇la~

Present Simple 是最簡單的時態，它的用途有三種：

1 用以表達一些重覆的動作或習慣：
E.g.1：We get up early every day.

Present Continuous Tense （現在進行式）
2. 表示一個與說話時同步進行的動作：
E.g.： Your father is working, don't disturb him.

3.Present Perfect Tense & Present Perfect Continuous Tense
1. 當說及一些事件發生於以前，並繼續進行至現在，我們都可以使用 Present Perfect Tense 或 Present Perfect Continuous Tense，意思上是沒有多大的分別。不過我們普遍都會偏用 Present Perfect Tense。

E.g.：I Have lived/have been living in this house for years／since 1992.
2. 當強調一個動作我們做了多少次或發生次數，我們會用 Present Perfect Tense：
E.g.： He has broken his arm four times before.

3. 當一個動作於過去發生，持續到現在，並有可能會繼續發生至將來，我們會用 Present Perfect Continuous Tense：
E.g.： Mr. Chan owns a garage. He has been repairing cars for a living since he left school.



4. 我們會用 Present Perfect Tense 來表達一個較長久，永恆的事情。以 Present Perfect Continuous Tense 來表達一個比較臨時，較短暫的動作
（不過這個特性就較少人會注意）。

E.g.： You have been working hard recently. You should take care of your health.
Simple Past Tense 是表達一個過去及已經結束的動作，而這個動作必須給予一個清楚的時間。簡單而言，就是如果我們在知道時間的情況下，我們會用 Past Tense，相反如果不知道時間，我們會用 Present Perfect （continuous）Tense，或 Past Perfect （Continuous）Tense，視乎情況。

E.g.：My brother has got a reply. He received the letter yesterday afternoon. It was mailed by DHL.
E.g.：I have had a meeting with Jill, it was great, we enjoyed so much.
Past Perfect Tense （過去完成式）

當我們想表達一個比 Simple Past Tense 更早發生的動作時，就會用上 Past Perfect Tense 或 Past Perfect Continuous Tense，現在先說 Past Perfect Tense。
這個 Past Perfect Tense 與 Present Perfect Tense 雖然名字很相似，但是用法卻有一點兒不同。Past Perfect Tense 不需要像 Present Perfect Tense 般注意什麼 "有沒有準確時間"，只要在相比下較 Simple Past Tense 早，便可以交給它去辦了。

E.g.：We were there at 9:00 a.m., but the bus had gone.
E.g.：I studied hard in library yesterday afternoon, because I had got a very bad result. If I don't work hard now, I will fail again.

為了加深概念，我們再看多兩個例子吧：
E.g.：He had left ten minutes ago.
E.g.：He left ten minutes ago.
http://hk.knowledge. yahoo.com/question/? qid=7006050702121

ALSO,,
http://www.crazyhill .com/hung/english/te nse.htm

參考資料:
YAHOO

Present tense: a habit, enernal truths
Present continuous: now, when, while, always +ing
Past : finished actions, yesterday
Past continuous: was/were +ing
Present perfect: have/has been +ed
Past perfect: had been + ed, use this form prior to past simple
Future: will, tomorrow, going to, will have, shall
Future continuous: will be +ing
e.g. Shall I phone you at 730pm? No, I'll having my dinner.
Future perfect: will have/has +ed