Compare these two sentences:

1. “I have a new car”.
2. “I have got a new car”

Do they have the same meaning?

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Yes, they do. Both have and have got can be used to express possession, but have got is considered to be more colloquial than have, and in more informal contexts, speakers even tend to drop have:
I’ve got a problem (informal)
I got a problem (very informal)
The only difference between them comes when we use negative or interrogative forms, because in sentence 2  have is an auxiliary verb, whereas in 1 it needs the auxiliary do in order to form interrogative or negative sentences:

1. “Do you have a new car?” “I don’t have a new car”.
2. “Have you got a new car?” “I haven’t got a new car”.

To see all the forms, have a look at this presentation:




In formal English, have can be used as an auxiliary in questions and negative sentences, but this form is not so much used as the other two.
Have you any brothers or sisters? instead of Do you have any brothers or sisters?

In the past tense, the got-forms are less common:
She had a headache last night. (Not *She had got a headache...).

Have got is not used in the infinitive, gerund or participle forms, have is used instead:
It’s nice to have a coat on when it’s cold. (Not: *It’s nice to have got...).

Have got is not used either in sentences with adverbs of frequency (always, usually, often...):
I’ve got a headache. But I usually have a headache at night. (Not *I’ve usually got a headache...).

Have to and have got to followed by an infinitive are used to express obligation. They are semi-modal verbs and similar in meaning to must, although not quite the same.
I have to go
I’ve got to go
I got to go
All these sentences mean the same, the only difference is that the second is less formal than the first and the last one is the least formal of all.
In informal English and also in songs we can hear gotta instead of got to. This new form is similar to other contractions that are now very common in English, such as gonna (going to) or wanna (want to). We can hear some of these in this song by The Black Eyed Peas: “I’ve got a feeling”.
 






Apart from the meanings of possession and obligation, have can also be found in collocations such as have a bath, have tea, have lunch, have dinner, have a test, etc., but that will be dealt with in another post.


Exercises:
Fill in the gaps with the correct form of have or have got

Negative and interrogative

Choose the best option

Correct the following sentences