Senin, 21 Februari 2011

[FCE] Past Simple, Present Perfect, Present Perfect Continuous

Past Simple and Present Perfect

The Present Perfect is the tense that links the past with the present.

Past Simple (past form)
Present Perfect
(present of have + past participle)
We use the Past Simple:
We use the Present Prefect:

For past habits of states, whether continuous or repeated:
Long ago, they built most houses out of wood.
He always caught the same train.
For actions or states in the past which have a connection with the present:
They have bought a new house. (= they can now go and live in it)
It’s just started to rain. (= now, so bring the washing in)

When the result of an action or state are obvious now:
You’ve split the coffee all over my trousers – look!
They’ve polluted the river. (= the fish are dead)

For repeated actions in the past, with words like often, rarely, seldom:
He’s often been to France.
With periods of time that have finished:
I read the newspaper this morning. (= it is now afternoon or evening)
He did a lot in his short life. (= he’s dead)
With periods of time that have not finished yet:
We’ve built 20 new schools this year. (= it is still this year)
He has done a lot in his short life. (= he’s alive and young)
For finished actions with time words like a year ago, last Sunday, last week, yesterday, etc.:
Watson and Crick identified the structure of DNA in 1953.
The first modern Olympic took place in Athens more than a hundred years ago.
For actions with expressions like already, before, ever, never, often, recently, still, yet, etc.:
Rain has already ruined the tomato crops.
Have you ever seen a UFO?
We still haven’t discovered life on other planets.
They haven’t sent an astronaut to Mars yet.

The choice between the Past Simple or Present Perfect depends on whether the action links the past with the present:
She often took the bus. (= but doesn’t any more)
She has often taken the bus. (= and so she might do it again)
Regular verbs end in –in in both the past Simple and the past participle (the form we use for the Present Perfect): worked, looked, played.

Present Perfect Continuous

We use the Present Perfect Continuous (present form of have + been + -ing) to talk about actions which started in the past and which continue up to the moment of speaking. We use it especially when we are interested in the duration of the action:

I’ve been waiting for a whole hour!
The Present Perfect emphasizes the idea of completion (= the homework is finished); we use the Present Perfect Continuous to indicate that the action has lasted for a period and is incomplete. Compare:

I’ve read the newspaper today. (= I’ve finished it)
I’ve been reading the Encyclopedia Britannia. (= I haven’t finished it yet)
Notice the difference between the Present Perfect Continuous and the Present Perfect:

Present Perfect
I’ve done my homework.

Present Perfect Continuous
I’ve been doing my homework.
We often use the Present Perfect Continuous with for and since:

Those potatoes have been boiling for and hour.
And the carrots have been boiling since three o’clock.

Source: Grammar & Vocabulary for First Certificate

Artikel Terkait:


Posting Komentar