[*englishbaby*]

I speak in English to my nephew now and then. He take medicine regulary . and I ask him: have you taken your medicine?. Or, before he goes to bed ,I ask him: have you brushed your teeth*

Should I ask him by useing simple past tense?which one is correct? :
"Did you brush your teeth?"
Or he gets up before me. While ı was having breakfast I ask him "did you have a breakfast ?
According to me. the present perfect tense is correct. Because it is important for me that whether he does that action. or else it isint important when he does that action.
Which one should I use?Simple past tense or present perfect?

[susan53]

Either.
If you want to see it as a past event, simple past - Did you.... This choice would be more commion in American English, I think.
If you see it as a past event with a present result (eg his teeth are now clean) and feel that it's the present result which is more important than the past event, then present perfect - Have you...?. This would be a frequent choice in British English.

The verb forms express two different meanings. Choose the meaning that you want to express.

Notice however that, whichever you choose, there's no a with breakfast : You could say either
Did you have (or Have you had) breakfast yet?
orDid you have (or Have you had) your breakfast yet?

[jakda]

The choice is definitely more common in American English. In America I constantly hear, "Did you eat yet?" After being here a while it's starting to become a lot easier on the ear. In the UK we would only say, "Have you eaten yet?"

[*englishbaby*]

I thank you very much indeed to susan and jakda Your explanations are very clear and simple. I like British English much more than American English because this language derived from Britain. I understand the difference. For example. My nephew wants to eat something when he arrive home after school I can ask him: have you washed your hands yet? ıf you havent washed them you cant eat ! ok many thanks

[susan53]

There is very little difference between British and American varieties of English, englishbaby. Or for that matter between those and Australian, New Zealand, Canadian, South African, Falklands Islands or any other variety of the language. There will be accent differences, some vocabulary differences, and a very few grammatical differences. But that happens within the country too. If I go to the North of England the accent is very different to my southern British accent. There are vocabulary differences - I'll use anyway while my Northern friends might say anyroad. And grammatical differences : I might say I was sitting, they might say I was sat. But these are all minor variations and you can usually count the number of the important ones on your fingers. The same with US/UK English. if you look at the posts on this forum, I'm sure you would generally have difficulty identifying the nationality of the writers just from the language they use. Unless one of the few differences happens to be used in the message, it's impossible to tell.

[destinyawaits]

The "Did you" or "Have you" distinction is one of those examples where the rules become really fuzzy. For example after seeing a movie with someone I'd ask, "did you enjoy the movie?" and never "have you enjoyed the movie?" Why? I'm not quite sure but "Did you" seems to go with expressions of satisfaction or dissatisfaction. Also in a question like "Did you brush your teeth?" the use of "Did you" seems to express some sort of expectation on the part of the questioner (that the person either hasn't brushed his teeth or was reluctant to do so) whereas "have you" sounds more neutral, just asking for information. Grammar rules only really scratch the surface of a language, they are like training wheels on a bike in my opinion.

[*englishbaby*]

Thank you very much.Suzan I know that there is little difference between Brisitsh and American English. I mean I prefer British vocabulary. For example I say "tap" instead of " faucet " or I say pavemenet not sidewalk...
Dear destinyaawaist thank you for your wxplanation . But I think we should say haave you enjoyed the film. after seeing a film. because the film has just finished and we cant use simple present. For example : you lost your key 2 minute ago and you are looking for your key. And you say "I have lost my key". The action has just finished and refers to this moment.I really confused. This subject simple past and present perfect is too complex for me. Because of that I asked anyway

[clevermae]

Past perfect tense describes an action that took place in the past before another past action. This tense is formed by using did with the past participle of the verb.

Present perfect progressive tense describes an action that began in the past, continues in the present, and may continue into the future.

[*englishbaby*]

Yes I know past perfect . That's simple. The confusing me that is the difference between present perfect and simple past tense. Because there isn't equivalance in my language.We have only one past tense
But these explanations became very useful for me. Thanks to evetybody.