Thì hiện tại hoàn thành

Thì hiện tại hoàn thành là một thì khá quan trọng trong tiếng Anh nhưng nó cũng khiến cho người học gặp nhiều khó khăn. Nguyên nhân là do nó dùng các khái niệm hoặc ý tưởng không tồn tại trong ngôn ngữ mẹ đẻ của họ. Thực tế, cấu trúc của thì hiện tại hoàn thành rất đơn giản. Vấn đề gặp phải đến từ cách dùng của thì này. Hơn nữa, có một số khác biệt trong cách dùng thì này giữa tiếng Anh Anh và tiếng Anh Mỹ.

Trong bài học này, chúng ta sẽ học về cấu trúc và cách dùng của thì hiện tại hoàn thành, cũng như cách dùng của for và since và sẽ có bài tập để giúp bạn hiểu rõ hơn.

Thì hiện tại hoàn thành thực sự à một thì thú vị và hữu dụng. Đừng cố gắng dịch thì hiện tại hoàn thành sang ngôn ngữ mẹ đẻ của bạn. Hãy cố gắng tiếp nhận các khái niệm của thì này và học để nghĩ về hiện tại hoàn thành. Bạn sẽ sớm cảm thấy thích nó thôi.

Cách thành lập thì hiện tại hoàn thành

Cấu trúc của thì hiện tại hoàn thành là:

subject	+	auxiliary have	+	main verb
		conjugated in Present Simple
		have, has		past participle

The auxiliary verb (have) is conjugated in the Present Simple: have, has

The main verb is invariable in past participle form: -ed (or irregular)

For negative sentences we insert not between the auxiliary verb and the main verb.

For question sentences, we exchange the subject and the auxiliary verb.

Look at these example sentences with the Present Perfect tense:

	subject	auxiliary verb		main verb
+	I	have		seen	ET.
+	You	have		eaten	mine.
–	She	has	not	been	to Rome.
–	We	have	not	played	football.
?	Have	you		finished?
?	Have	they		done	it?

Contraction with Present Perfect

When we use the Present Perfect in speaking, we often contract the subject and auxiliary verb. We also sometimes do this in informal writing.

I have	I’ve
You have	You’ve
He has She has It has John has The car has	He’s She’s It’s John’s The car’s
We have	We’ve
They have	They’ve

• You’ve told me that before.
• John’s seen Harry Potter.

In negative sentences, we may contract the auxiliary verb and “not”:

• You haven’t won the contest.
• She hasn’t heard from him.

He’s or he’s??? Be careful! The ‘s contraction is used for the auxiliary verbs have and be. For example, “It’s eaten” can mean:

• It has eaten. (Present Perfect tense, active voice)
• It is eaten. (Present Simple tense, passive voice)

It is usually clear from the context.

How do we use the Present Perfect tense?

This tense is called the Present Perfect tense. There is always a connection with the past and with the present.

We use the Present Perfect to talk about:

• experience
• change
• continuing situation

Present Perfect for experience

We often use the Present Perfect to talk about experience from the past. We are not interested in when you did something. We only want to know if you did it:

I have seen an alien. He has lived in Bangkok. Have you been there? We have never eaten caviar.
past	present	future
!!!
The action or state was in the past.	In my head, I have a memory now.

Connection with past: the event was in the past
Connection with present: in my head, now, I have a memory of the event; I know something about the event; I have experience of it

Present Perfect for change

We also use the Present Perfect to talk about a change, or new information:

I have bought a car.
past	present	future
–	+
Last week I didn’t have a car.	Now I have a car.

John has broken his leg.
past	present	future
+	–
Yesterday John had a good leg.	Now he has a bad leg.

Has the price gone up?
past	present	future
+	–
Was the price $1.50 yesterday?	Is the price $1.70 today?

The police have arrested the killer.
past	present	future
–	+
Yesterday the killer was free.	Now he is in prison.

Connection with past: the past is the opposite of the present
Connection with present: the present is the opposite of the past

Americans do use the Present Perfect but less than British speakers. Americans often use the Past Simple tense instead. An American might say “Did you have lunch?”, where a British person would say “Have you had lunch?”

Present Perfect for continuing situation

We often use the Present Perfect to talk about a continuing situation. This is a state that started in the past and continues in the present (and will probably continue into the future). This is a situation (not an action). We usually use for or since with this structure.

I have worked here since June. He has been ill for 2 days. How long have you known Tara (for)?
past	present	future
The situation started in the past.	It continues up to now.	(It will probably continue into the future.)

Connection with past: the situation started in the past.
Connection with present: the situation continues in the present.

For and Since with Present Perfect tense

We often use for and since with perfect tenses:

• We use for to talk about a period of time: five minutes, two weeks, six years
• We use since to talk about a point in past time: 9 o’clock, 1st January, Monday

for	since
a period of time	a point in past time
– – – – – – – – – – – –	– • – – – – – – – – – –
20 minutes	6.15pm
three days	Monday
6 months	January
4 years	1994
2 centuries	1800
a long time	I left school
ever	the beginning of time
etc	etc

Look at these example sentences using for and since with the Present Perfect tense:

• I have been here for twenty minutes.
• I have been here since 9 o’clock.
• John hasn’t called for six months.
• John hasn’t called since February.
• He has worked in New York for a long time.
• He has worked in New York since he left school.

For can be used with all tenses. Since is usually used with perfect tenses only.