Talking about verbs

Now that you're studying English at a high 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(过去式) and the present perfect(现在完成时).

The past tense is indicated by use of the past tense marker,  represented here by V(d).

Here are some examples of regular verbs and there past tense forms.

So ,as you can see,for regular verbs, the past tense form 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 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 use 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 it 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(不是事实) condition,which means it goes against what we konw or believe.

Look at these 2 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.

(There was a big sale last week,so we all went shopping.

If that flight left a few minutes later,we could take the next shuttle bus.)

Talking about verbs 2

When we talk about experience or results ,we use the present perfect form.

This form uses have followed by the part participle(分词).

For regular verbs,This participle is identical(相同) 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 sentence not the verb.

It emphasizes(强调) condition,experience or results rather than actions or events.

In this 2 examples we see the contrast(对比).

"She has already left the hotel."

"She left the hotel a few minutes ago."

The top sentence gives 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 nowpart 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 events or acts and the perfect form expresses experience or conditions.

When we use the perfect form of the verb,we focus on the state of the subject and not an action or event.

(In high school,John wasn't a very good student .

In fact,he was one of the worst stidents.

When It came time to go to university ,nobody expected him to pass the entrance examination .

However ,He proved them wrong and did well enough to get into a top university .

He enjoyed his.studies and graduated a few months ago.

Now that he has graduated ,he's ready to get a job.)

Note that the past form expresses events at specific points or period of time,such as last year or the past five years.

These events are distancedfrom the speaker's point of view.

"He worked at several companies.(In the past)"

"He finished the project last week.(In the past,last week.)"

THe perfect form expresses the state of something from the speaker's point of view not distanced In time.

These two sentences are incorrect and confusing because they give two different points of view.

Here are some sentences that use the perfect form.

Some are sample 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.

(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.)