ABOUT TENSES!!

Lesson 33 : Future Prefect Tense

§ Future Prefect Tense
動詞的將來完成時態的形態是：

will ( shall ) have + 動詞的過去分詞
動詞的將來完成時態表示：

將來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，動詞要用將來完成時態；敘述後面的動作
或狀態，動詞要用一般現在時態。

※ 圖示：

過去 現在 將來
_________________│____________________________________
│ │
future perfect simple present (simple future)
例如：

We will have completed the work before you come.
﹝在你來之前，我們將完成工作。﹞
※「你來」在將來發生，應用 "You will come" ( Simple Future ) ，
但習慣上卻用 "You come" ( Simple Present ) 來代替。
這種情況是：
"Simple present tense in form but Simple future in meaning"
﹝形式上是一般現在時態，但意義上是一般將來時態﹞
He will have studied English for five years by the end
of next month.

* "by the end of next month" 稱「時間短語」"Phrase of time"，
使用了，可不用從句。

We will have played ball when you come.
或 when you come, we will have played ball.
When I have taken my supper, I will take a walk with you.
﹝當我吃完晚餐時，我將和你散步。﹞
※「我吃完晚餐」在將來完成，應用 Future Perfect Tense，
但可以用 Present Prefect Tense 代替。
這種情況是：
" Present perfect tense in form but future perfect tense in meaning."
﹝形式上是現在完成時態，但意義上是將來完成時態﹞
After I take my supper, I will take a walk with you.
※若用 "After" 一詞，則可以用 Simple Present Tense 來代替。
這種情況是：
"Simple present tense in form but present perfect tense in meaning."
﹝形式上是一般現在時態，但意義上是現在完成時態﹞

He says that he will have graduated from a university
before you return home.

1) what does it mean?
* it means that it will be perfected(done) in the future.

2) when do you use it?
* when you want to compare the sequence of 2 future events.

eg. if we re still stuck in the traffic for any longer, the concert would(will) have been finished before we arrive!

3)*'has been slept/talked' are strange phrases to hear, 'has been eaten' is in present perfect passive voice.

eg. the fish has (just) been eaten by the shark!