1.在「現在」這個時間點之前「已經完成」的事，但是「時間點不重要」
2. 在「現在」這個時間點之前「重複」從事某活動的「次數」，但每一次活動的「時間點不重要」
3. 某情況在過去的某個時間點發生並「持續」到「現在」
光看這樣簡短的文字敘述相信讀者們大概還是霧煞煞，以下就用三張圖解與生活實例詳細說明現在完成式的使用情境。
現在完成式的使用情境1.在「現在」這個時間點之前「已經完成」的事，但是「時間點不重要」
A: Have you ever been to Japan?
B: Yes, I have.
A: Great! When did you visit Japan?
B: I visited Japan last summer.
A: Where did you go?
B: I went to Tokyo.
例如: 你問對方Have you ever been to Japan? 「你去過日本嗎?」要表達的是你想知道到現在之前對方去過日本了沒? 但是你並沒有問對方何時去日本?也就是說時間點不重要，這樣的語句要用現在完成式來說； 如果你要問對方何時去日本，也就是想知道明確的時間點，必須說When did you visit Japan? I visited Japan last summer. 要用過去簡單式來表達。換句話說，我去年夏天去日本這件事情，是發生在過去的時間點沒錯，但是隨著說法的不同，用的時態就不同。
2. 在「現在」這個時間點之前「重複」從事某活動的「次數」，但每一次活動的「時間點不重要」
A: Have you ever been to this restaurant?
B: Yes, I have. I have eaten at this restaurant three times.
A: When did you last come here?
B: I came here a month ago.
例如:今天你和你的朋友到一家餐廳吃飯，你的朋友問你說：「你有來過這家餐廳嗎?Have you ever been to this restaurant?」你回答說：「我來過這個餐廳吃飯三次了I have eaten at this restaurant three times.」你表達的是到目前現在這個時間點你來過這家餐廳三次，但是每一次來的時間點你並有提，時間點不重要，這樣的情境也會用現在完成式。同第一點中敘述的概念，如果你很明確地說出過去來過這家餐廳的時間點，那就要用過去簡單式表達。When did you last come here? 你上次什麼時候來這家餐廳I came here a month ago. 我一個月以前來過這裡。
3. 某情況在過去的某個時間點發生並「持續」到「現在」
A: Do I need to get a new cell phone?
B: How long have you had your cell phone?
A: I have had my cell phone for 2 years.
B: I see. If you don’t have to live within a tight budget, you can get a new one.
Lily最近在考慮到底要不要買一支新手機，因為她的手機用起來不太好用，她與她的好友商量，朋友問她手機用多久了? 這句英文要用現在完成式來表達How long have you had your cell phone? 我用這支手機兩年了I have had my cell phone for 2 years. Lily是在兩年前買這支手機的，然後一直使用到現在，現在還在用這支手機。Lily bought her cell phone two years ago. She still has her cell phone today. 從過去到現在Lily使用這支手機兩年了。
再舉另外一個例子: 在人生的旅程上我們會認識很多人，有些人會成為我們一輩子的好朋友，當要問說你認識你的好朋友多久了? 英文也是要用現在完成式表達:
How long have you known your best friend?
I have known my best friend for twenty years.
I have known my best friend since I was a kid.
我在二十年前還是個小孩時遇到我最好的朋友，至今我們仍然是朋友，我們當朋友二十年了。I met my best friend twenty years ago. I still know her today. We are friends. We have been friends for twenty years. 也就是說，現在完成式用來表達某個活動從過去持續到現在，這邊要注意的是「自從何時起」英文是since + 具體的時間點，大家不要用from喔!那是中式英文，如果是想表達一段時間(如: 二十年 for twenty years、大約三周for about three weeks、很久 for a long time)英文要用for + 一段時間。
現在完成式的基本句型動詞的形態可以分為: 動詞原型(simple form)、過去式(simple past)、過去分詞(past participle)、現在分詞(present participle)
動詞原型過去式過去分詞現在分詞bewas, werebeenbeingeatateeateneatinghopehopedhopedhopinghavehadhadhaving動詞原型就是動詞原本的樣子，大家在字典中看到的形態，動詞過去式用於過去簡單式中，過去分詞用於完成式與被動式中，現在分詞則用於進行式中，現在完成式就是用have/has +P.P. (過去分詞)的形態來表達，這裡要注意的是have/has +P.P中的 have/has並不是「擁有」的涵義，而是一個「助動詞」，以下列表說明現在完成式的肯定句、否定句、疑問句的基本句型及常用字詞：
1.現在完成式肯定句人稱現在完成式肯定句第一人稱單數第一人稱複數
I have been here since yesterday.We have been here since yesterday.
第二人稱單數第二人稱複數
You have been here since yesterday.第三人稱單數He has been here since yesterday.She has been here since yesterday.
It has been here since yesterday.
第三人稱複數They have been here since yesterday.這邊舉一個學生常搞混的例子:
I have already had dinner. 我已經吃晚餐了
很多學生看到這個例子可能心想：「奇怪！怎麼兩個have放在這裡?」，這邊already之前的"have"是助動詞，後面的"had”是吃晚餐的"吃"，因為放在have這個助動詞之後要用過去分詞had的形態，關於already這個字詞的用法，想更深入了解的可以閱讀文章「中式英文餐飲篇特輯讓你吃出英文力。」
2.現在完成式否定句我從今早起床之後還沒吃東西
I have not eaten since I got up this morning.
I haven’t eaten since I got up this morning.
我姊姊從今早起床之後還沒吃東西
My sister has not eaten since she got up this morning.
My sister hasn’t eaten since she got up this morning.
have not-> 可以縮寫成 haven’t
has not-> 可以縮寫成 hasn’t
3. 現在完成式疑問句你寫作業了嗎?
Have you done your homework?
Yes, I have. I have done my homework.
No, I haven’t. I haven’t done my homework yet.
他寫作業了嗎?
Has he done his homework?
Yes, he has. He has done his homework.
No, he hasn’t. He hasn’t done his homework.
4. 常與現在完成式連用的字詞有: ever曾經、never從未、already已經、yet尚未、still仍然、just剛才、so far到目前為止、recently 最近，但不代表這些字只能用在現在完成式喔! 以下列出例句說明:
Have you ever met a famous writer? 你有碰過一個有名的作家嗎?
No, I have never met a famous writer. 不，我從未見過一個名作家
I have already read that book.那本書我讀過了
John hasn’t finished his project yet. John尚未完成他的專案
Alice started to write a new story last month, but she still hasn’t finished it. Alice上個月開始寫一個新故事，但她仍未寫完
I have just drunk a cup of coffee. 我剛喝完一杯咖啡
We have had three tests so far this week. 到目前這周為止我們已經考了三場考試
Robert has recently bought a new car. Robert最近買了一輛新車
練習題:
1.A: (you, get drunk, ever)_____________________at a party?
B: No, I ________. I (get drunk, never) ______________at a party.
2. A: (you, meet, ever) __________________someone famous?
B: Yes, I _____. I (meet) ______________someone famous.
3. A: (he, keep, ever) ___________________a diary?
B: Yes, he ______. He (keep) ________a diary.
4. I (know) _______Winnie ever since we (be) ________in junior high school.
5. Peter (visit) _____________Greece three times since he (start)_______ his new job.
6. So far, I (drink) __________ two cups of coffee and three cups of tea.
7. Betty (have) _____________a lot of problems with her new scooter ever since she (buy)_______it.
8. A: (you, ever, change)______________a diaper?
B: No, I ________. I (change, never) _________a diaper.
答案:
1.Have you ever got drunk, haven’t, have never got drunk
2. Have you ever met, have, have met
3. Has he ever kept, has, has kept
4. have known, were
5. has visited, started
6. have drunk
7. has had, bought
8. Have you ever changed, haven’t, have never changed
現在完成式與過去簡單式例子說明例一:
Mr. Potter was in Phoenix for three years.
Mr. White has been in Phoenix for three years.
這兩個句子看似類似但是使用的時態和表達的文意全然不同!Mr. Potter was in Phoenix for three years. 是使用過去簡單式來表達，也就是這件事情開始並結束於過去，Mr. Potter現在已不在鳳凰城，所表現出的時間圖如下:
Mr. White has been in Phoenix for three years. 是使用現在完成式來表達Mr. White已經在鳳凰城三年了，他現在還在鳳凰城，所表現出的時間圖如下:
例二:
Sue drank a cup of black tea two hours ago.
Sue has already drunk a cup of black tea.
Sue drank a cup of black tea two hours ago. Sue兩小時前喝一杯紅茶，有明確的過去的時間點，用過去簡單式來表示。
Sue has already drunk a cup of black tea. Sue已經喝了一杯紅茶，這句話用現在完成式表達，我們只知道到「現在」這個時間點為止Sue已經喝了一杯紅茶，但我們並不知道她何時喝紅茶，時間點並不重要，句意強調的是Sue「已經」喝了一杯紅茶這個動作。
現在完成式與過去簡單式練習題1.Ben has bought a new computer _________. A) last Monday B) already.
2. I have seen that movie _________. A) three days ago B) recently
3. John hasn’t seen that movie _______. A) yet B) last night
4. I went to a Japanese restaurant _______. A) so far B) yesterday
5. I have been to this town _________. A) several times B) yesterday
6. A: Have you ever been to Norway?
B: Yes, I ______. I (be) _____to Norway three times.
A: When did you last (visit) ______Norway.
B: I (be) ________ there three month ago.
7. A: Have you ever (eat) ________at the Skyblue cafe?
B: Yes, I ______. I (eat) _________there many times. Actually, my coworker and I (eat) ________dinner there last night.
8. A: This novel is so interesting. Would you like to read it?
B: Thanks, but I (read, already) __________it. I (read) ______ it a week ago.
9. My brother is a web designer. He (create) ________ a lot of plain but easy-to-use websites. Last week, he (set up) _______a new website about umbrellas.
10. She (see, never) _______ the Northern Lights in her life.
11. Last winter, she (see) _______the Northern Lights for the first time in her life.
12. Mr. Smith taught at this university for five years.
Mr. Huang has taught at this university for five years.
問: 誰現在還在這間大學教書?
13. Gary lived in England for three years.
Carol has lived in England for three years.
問: 誰現在還住在英國?
14. It’s 11:30 A.M. Jay has been at the library since 10:00 A.M.
Lisa was at the library from 10:00 A.M. to 11:00 A.M.
問: 誰現在還在圖書館?
15. In his lifetime, Oscar had several cars.
In her lifetime, Sandy has had several cars.
問: 誰還活著?
答案:
1. B 2.B 3. A 4. B 5. A
6. have, have been, visit, was
7. eaten, have, have eaten, ate
8. have already read, read
9. has created, set up
10. has never seen
11. saw
12. Mr. Huang
13. Carol
14. Jay
15. Sandy
現在完成式常見問題現在完成式公式?現在完成式的公式是have 或 has +過去分詞(P.P. )，前面的主詞是第三人稱單數(he, she, it) 則用has +P.P.其他則使用have +P.P.
現在完成式例句?肯定句I have read this novel. He has read this novel.否定句 I haven’t read this novel. He hasn’t read this novel.疑問句 1.Have you read this novel? Yes, I have. No, I haven’t.2.Has he read this novel? Yes, he has. No, he hasn’t.3. What have you done since you got up this morning?
現在完成式被動?現在完成式被動語態是 have been + P.P. 或has been +P.P. 例如: The letters have been sent by Joe. The apple has been eaten by Sue.
現在完成式與過去簡單式的差別?現在完成式表達到現在為止已經完成的事情，時間點不重要，而過去簡單式用來表達開始於過去結束於過去的事情，會有明確的過去的時間。例如: I have already finished the project. 到目前為止我已經完成專案，但並沒有提時間點；I finished the project yesterday. 我昨天完成專案，有昨天這個明確的過去時間詞用過去簡單式表達。
現在完成式與過去完成式的差別?現在完成式表達到現在為止已經完成的事情用have/has +P.P.來表達，例如: I have finished my homework. 我到目前為止已經完成我的作業了；過去完成式表達截至到過去的某個時間點之前已經完成的事情，用had+P.P.表達，例如: When I got to the theater, the movie had already started. 兩件事情都發生在過去，先發生的事情用過去完成had+P.P.後發生的事情用過去簡單式，電影先開始然後我才抵達劇院，在我抵達劇院電影已經開始了。
參考書目:
Azar, Betty Schrampfer.Understanding and Using English Grammar. 3rd ed. New York: Pearson Education, 1999.
Azar, Betty Schramfer. Fundamentals of English Grammar. 4th ed. New York: Pearson Education, 2011