I/we/you/they worked.
He/she/it worked.
2. Usage of the present perfect tense
(1) indicates actions that have occurred and have an impact or result on the present. This situation is usually not used with any adverbial of time.
Sorry, I lost my key. I can't open the door.
Sorry, I lost my key. The door won't open. When was the key lost? I don't know. The key is the result, and the result is that you can't open the door without the key. )
If you want to see her, you must come tomorrow.
She left. If you want to see her, you must come again tomorrow. When did she leave? You don't need to know. The key is the result. She's not here. )
(2) indicates an action or state that occurred at a certain moment in the past and continues to the present. This situation is often used with adverbials indicating a period of time.
We have lived here since last October.
We have lived here since last October.
She has studied English for five years.
She has studied English for five years.
3. The adverbial of time in the present perfect tense
(1) The present perfect cannot be used with past time, such as yesterday, last year, two years ago, 1999 1999, just now, etc.
(2) The adverbial of time used with the present perfect tense is closely related to the present. Common adverbials of time are:
Adverbial indicating a period of time
For a long time ... in the past few years;
(2) Adverbs expressing past time
Just before, before, recently
(3) Adverbs expressing uncertainty
There have been, however (used in interrogative sentences), never, ever, no ... however. ...
(4) including the adverbial of present time
Today, this week, this year, now, so far.
The train just left.
The train just left.
I have seen this film before.
I have seen this film before.
Now I have finished my work.
Now I have finished my work.
Did you see Tom today?
Did you see Tom today?
4. Verbs in the present perfect tense: Instantaneous verbs are used in the present perfect tense and cannot be used with adverbials such as for and since to indicate a period of time.
He has left America.
He has left America. (Instantaneous verbs cannot be used with duration. )
It has been five years since she left America.
It has been five years since she left America. (The progressive verb can be used with duration. )
The common verbs are: come, go, start, arrive, leave, stop, die, get married, borrow, return, buy, join and become.
5. Question of interrogative adverbs in the present perfect tense: The present perfect tense can be used with interrogative adverbs where, why, how, etc. But it cannot be used with the interrogative adverb when.
Where have you been?
Where have you been? (present perfect tense)
When did you buy the computer?
When did you buy this computer? (simple past tense)
6. Other usages of the present perfect tense
(1) Replace the future perfect tense in conditional adverbial clauses and time adverbial clauses.
I'll go with you when I make the model plane.
I'll go with you as soon as I finish the model plane.
The present perfect tense can be used in the sentence "This is the first time …".
This is the first time I have seen this kind of film.
This is the first time I have seen such a movie.
(3) the difference between being there and being there.
① Yes ... The key is that people have left the starting point and there is no way to know whether they have reached their destination.
Jack has gone on holiday. He went to France.
Jack has gone on holiday. He went to France.
Yes ... the key is to have been somewhere and have left that place.
Mr. Chen is back from vacation. He has been to Beijing.
Mr. Chen came back from vacation and went to Beijing.
7. Comparison between the present perfect tense and the general past tense
(1) The present perfect tense focuses on the influence and result of an action on the present and the connection between this action and the present. The simple past tense pays more attention to the pure fact of a verb.
(2) The present perfect tense is used to provide new information. But if you want to continue, you usually need to use the simple past tense.
example
Mom, I'm hurt. Mom, I'm hurt.
How did you do that? How did you get hurt?
I fell off my bike.
(3) Some idioms, such as
Where is Kate? Where is Kate?
She has gone to Singapore. She has gone to Singapore.
Where have you been? Where have you been?
I have been to the library. I just went to the library.
8. "Already" is often used with the present perfect tense. But it is also used with other tenses.
Used with the present perfect tense.
I have taken a big step in this direction.
I have taken a big step in this direction.
(2) Used with the simple present tense
It's already eight o'clock.
It's already 8 o'clock.
(3) Used with the simple past tense
I am happy for her; She looks much better.
I'm so happy for her; She looks much better.
(4) Used with the simple future tense
I will be in Tokyo by this time tomorrow.
By this time tomorrow, I will have been in Tokyo.
5. Used with the present continuous tense.
Britain is already mining a small amount of coal.
Britain is already mining a small amount of coal.
Used with the past continuous tense.
The train has already started.
The train has already started.
(7) Used with the past perfect tense
Jim had already left when I called.
Jim had already left when I called.