THE DIFFERENCE BETWEEN AMERICAN ENGLISH AND BRITISH ENGLISH

Use of the Present Perfect
In British English the present perfect tense is used to express an action that has occurred in the recent past that has an effect on the present moment.For example:
I’ve (I have) lost my key.Can you help me look for it?In American English the following is also possible:I lost my key.Can you help me look for it?
Other differences involving the use of the present perfect in British English and simple past in American English include already,just and yet.
British English:
I’ve already seen that film.
Have you finished your homework yet?
American English:
I already saw that film or I’ve already seen that film.
Did you finish your homework yet?or Have your finished your homework yet?
Possession
There are two forms to express possession in English “have” or “have got.”
Have you got a car?
He hasn’t got any friends.
He doesn’t have any friends.
She has a beautiful new home.
She’s got a beautiful new home.
While both forms are correct,“have got” (have you got,he hasn’t got,etc.) is generally the preferred form in British English while most speakers of American English use “have” (do you have,he doesn’t have,etc.)
The verb “get”
The past participle of the verb “get” is “gotten” in American English.Example:He’s gotten much better at playing tennis.British English:He’s got much better at playing tennis.
Prepositions
There are also a few differences in preposition use including the following:
American English:on the weekend; British English:at the weekend.
American English:on a team; British English:in a team.
American English:Please write me soon; British English:Please write to me soon.