Now that you're studying English at a higher level,you need to be able to talk about the language itself.
One of the biggest areas of confusion for students is the difference between the past tense and the present perfect.
The past tense is indicated by use of the past tensen marker,represented here by V(d).
Here are some examples of regular verbs and their past tense forms.
So as you can see, for regular verbs the past tense forms is indicated by the addition of an -ed at the end of the verb.
However, some of the most common verbs in English are irregular ,so it's important to learn them.
Here are some examples :
Altogether there are over 200 irregular verbs in normal use.
Many people think that the past tense form only indicates past time.
However, that is only one of the possible meanings.
The past tense form is also used to express something that is unlikely or imaginary,from the speaker's point of view.
Here is an example: He wishes he had a car.
The fact is that he doesn't have a car,so the use of "had" indicates that isn't real:It's imaginary.
If he had a car,he could drive us to school.
Again he doesn't have a car,so he can't drive us to school.
This condition expresses something that isn't a fact.
It's a counter-factual condition,which means it goes against what we know or believe.
Look at these two sentences:
Both sentences are correct, but there is a difference in meaning.
In the top sentence,the condition that she waits is more likely from the speaker's point of view.
In the bottom sentence, the speaker thinks it's less likely that she's going to wait.
When we talk about experience or results,we use the present perfect form.
This form uses have followed by the participle.
For regular verbs,this participle is identical to the past tense form.
For irregular verbs,this participle is often different.
When we use the perfect form,the primary focus is on the subject of the sentences,not the verb.
It emphasizes condition,experience or results rather than actions or events.
In these two examples,we see the contrast:
The top sentence give the condition or state of the subject and the bottom sentence expresses an event.
The top sentence describes the condition of the subject of the sentence,she,rather than an event.
The fact that she has left the hotel is now a part of her experience,or state of being.
The bottom sentence expresses the action,or event:she left,which is something she did.
In general,the past tense form expresses of events or acts,and the perfect form expresses the experience or conditions.
When we use the perfect form of the verb, we focus on the stae of the subject and not an action or event.
Note that the past form expresses events at specific points or periods of time,such as last year or the past five years.
These events are distanced from the speaker's point of view.
The perfect form expresses the state of something from the speaker's point of view,not distanced in time.
These two sentences are incorrect in confusing because they give two different points of view.
Here are some sentences that use the perfect form.
Some are simple,such as the first one,and some are complex,like the last one.
The last one is complex because it combines many verb forms,including the passive.
(repeat)
There's going to be a sale next week,so I hope she doesn't go shopping tomorrow.
If that flight leaves on time, we're going to miss it,so let's run.
He may have been injured in the explosion.
The game has started already.
He may have taken his computer with him,but i'm not sure if he did or not.
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