What is the exact Difference ?

[Mr_jim]

Could you please tell me the exact difference between following sentences...

1> I "have to" go home early tonight
2> I "have got to" go home early tonight
3> I "got to" go home early tonight
4> I "gotta go" home early tonight

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[Rusty]

Could you please tell me the exact difference between following sentences...

1> I "have to" go home early tonight
2> I "have got to" go home early tonight
3> I "got to" go home early tonight
4> I "gotta go" home early tonight



1> I "have to" go home early tonight
2> I "have got to" go home early tonight
3> I "got to" go home early tonight
4> I "gotta go" home early tonight
All these sentences have the same meaning.
I have read that 1. is more common in Am. Eng. and 2. is more common in Br. Eng. 3. can be used for present or future, but the meaning is different when used for past.
Example: I got to go now. I got to go tomorrow.
But, in the past "got to" means "to have the opportunity" or "to be allowed."
Example: I got to go to the movies last night because my sister agreed to baby-sit for me.
We got to go to the game because our friend's wife was sick and they gave us their tickets.
4. I am not sure where the line is drawn between informal, slang and slurred contraction. Gotta, wanna, gonna and dunno come in these categories.

[Mr_jim]

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In the sentence below:

I "got" to go some early tonight.


The verb "got" is in Past tense (Past tense of 'get').

But as you said, we can still use it in 'present' & 'future' tense.
It is a bit confusing for me.

Could you tell me why is it so?

[Pete]

Let me give my thoughts... The use of "got" in a present/future sense, as "I gotta go" or "I got to go" is certainly non-standard, but you hear it a good deal in very informal, casual speech. My theory is that it is a case of leaving out the "have" or "ve" in "I have got to go" or "I've got to go", where the present perfect is common and correct. People probably do this since it is also correct and means the same to say "I have to go", and they just replace the "have" with "got".

I think this is basically an idiom that is not part of standard English; I don't think it generalizes to any other cases or any pricniple of English grammar.