咩叫Perfect Tense？

Past Perfect Tense
動詞的過去完成時態的形態是：had + 動詞的過去分詞
動詞的過去完成時態表示：

過去某一時間之前已經完成的動作或狀態
使用這種時態，多會涉及兩個動作或狀態。一個在前，一個在後。
敘述前面的動作或狀態，動詞要用過去完成時態；敘述後面的動作
或狀態，動詞要用一般過去時態。

例如：

I had taken my supper when he arrived.
﹝當他到達時，我已吃完我的晚餐。﹞
※ 上述句子涉及兩個動作，一是「他到達」，二是「我吃晚餐」。
「我吃晚餐」在前，要用過去完成時態；「他到達」在後，要用
一般過去時態。

※ "I had taken my supper" 是主句， "when he arrived" 是從句
﹝副詞從句﹞。

※ 圖示：

過去 現在 將來
_________________________│__________________________
│ │
past perfect simple past
Had you finished your work when I visited you yesterday?
When I reached the station, the train had already started.
He said that his father had returned to America.
After I had done my work, I played tennis.
※ 若用了 "After" 這個詞，可不用過去完成時態，因已有「之後」
的含意。即：

After I did my work, I played tennis.
在這種情況下，"After I did my work"是：
" Simple past Tense in form, but past perfect Tense in meaning."
﹝形式上是一般過去時態，但意義上是過去完成時態﹞
同樣，I had seen your father before I went.亦可寫成：

I saw your father before I went.
用英文表示「我看電視之前已完成功課」，可以有多種方式：

1. When I had finished my homework, I watched television.
2. I had finished my homework when I watched television.
3. I had finished my homework before I watched television.
4. I finished my homework before I watched television.
5. After I had finished my homework, I watched television.
6. After I finished my homework, I watched television.
7. I finished my homework and I watched television.
﹝時間順序法﹞
※ 「時間順序法」：按事件的先後次序連接起來。
如果涉及三件或以上的事件，就更需要用這種方法了。例如：

I reached the station, the bell rang and the train started.

The perfect aspect is a grammatical aspect that refers to a state resulting from a previous action (also described as a previous action with relevance to a particular time, or a previous action viewed from the perspective of a later time).

The perfect aspect is not the same as the perfective aspect. See Grammatical aspect#Confusing terminology: perfective vs. perfect.

For example, "I have eaten lunch" implies both that a previous action happened ("I ate lunch") and that a current state resulted ("I am full"). This differs from the simple "I ate lunch", which implies only that an action happened, with no relevance to the present. The form "I have eaten" is referred to as a present perfect, meaning present tense, perfect aspect. (It is considered present tense instead of a past tense because the resulting state is in the present.)

In English, the perfect aspect can be combined with any simple tense (past, present or future), yielding perfect tenses that are formed using the conjugations of the auxiliary verb have and a verb:

Present perfect: I have overcome, passive I have been overcome.
Past perfect (pluperfect): I had overcome, passive I had been overcome.
Future perfect: I will (or shall) have overcome, passive I will have been overcome.
In addition to these, we can distinguish the three perfect progressive tenses:

Present perfect progressive: I have been overcoming,
passive I have been being overcome.

Past perfect progressive: I had been overcoming,
passive I had been being overcome.

Future perfect progressive: I will (or shall) have been overcoming
The perfect aspect can also be combined with various modal auxiliary verbs, such as would, should, could, may or might:

Conditional perfect: I would have overcome, passive I would have been overcome.
should-perfect: I should have overcome, passive I should have been overcome.
Progressives can likewise be formed from these:

Conditional perfect progressive: I would have been being overcome
should-perfect progressive: I should have been being overcome
The various perfect progressive passives are a fairly recent addition to English, and some speakers still find them questionable or even ungrammatical.[citation needed]