http://en.wikipedia.org/wiki/Grammatical_case The thing is that it is in English "you". In German there is a difference. There is a guideline rule that says if the verb benefits the object, it is dative. This does not always apply however. In the case of help it fits. The person being helped benefits but if you "see" someone, there is no positive effect.
Thanks, but I still do not understand. When you say "case" what are you talking about. When we in English (American) say case, we mean whether it is a capital letter or lower "case." I don't see the difference between the two sentences "I help you" versus "I see you." Can you explain why they are not the same "case" dative or accusative? It would seem that they both should be accusative. And is dich or dir always used in your examples or can one say "ich helfe sie." Maybe I am thinking too much? :)
Grammatical "case" is a concept in English too, and it's nothing to do with upper/lower case of letters. E.g. http://en.wikipedia.org/wiki/Grammatical_case
English doesn't have cases for most nouns, which makes it hard for us when learning other languages. We do have cases for pronouns though, so it can help to think of this. For instance I can't say "The cat sees I" or "Me sees the cat". Instead I have to say "I see the cat" and "The cat sees me". The pronoun I/me changes case depending on whether I am the subject or the object or the sentence. We/us is the same.
In german even "the" changes case so "the" in "the cat" in the sentences above would be different words. It also has gender (different words for "the" man and "the" woman) so German has something like 5 words for "the" where English just has one.
Der/die/das/etc. = "the"
This means a specific thing. The apple that is over there. That one, not any other.
Ein/eine/etc. = "a/an/one"
This means any one of the thing. It doesn't matter which of the apples, just bring me one of them.
The first group that mean "the" are called definite articles. The second group that mean "a/an/one" are called indefinite articles. The articles are inflected (change their endings) to match the gender and case of the nouns that they refer to.
You know how in English you say "I see him" and "He sees me"? You can't see "Me see he" or "Him sees I"?
The words change to show their role in the sentence -- whether they're the doer or the thing that "undergoes" the doing (here: the seeing).
"I" and "me" are two different case forms of the same word, as are "he" and "him".
German has this as well, but it has four cases instead of just two as in English.
The nominative case is used for subjects -- like "I" or "he". The person or thing that does the action.
The accusative case is used for direct objects -- the person or thing that undergoes or "suffers" the action. (As well as in various other situations.)
English has cases only in the pronouns, but in German, cases are much more alive and widely used, so you won't get around them.
Sort of. In the same way that "he" and "him" mean the same thing -- they both refer to a single male.
But you can't mix them and say "Him gave me a book" or "I saw he last night".
ein Apfel is the nominative case, which you would use e.g. when it is the subject of a verb, but here the apple is the object of the verb and so has to be in the accusative case.
Apfel is masculine -- the only gender in which the accusative case looks different from the nominative in German. And in this case, it's einen Apfel in the accusative.
Some verbs change the vowel in their stem in the du and er, sie, es forms, usually from e to i or ie or from a(u) to ä(u).
essen happens to be one of them -- so it is du isst and er isst with an i rather than e.
It's just something you have to learn -- for example, essen, fressen, messen form er isst, er frisst, er misst but pressen forms er presst. So you can't tell just by looking at a verb form whether it will do this vowel change or not.
The tips and notes for this unit, https://www.duolingo.com/skill/de/Accusative-Case/tips-and-notes , give the complete conjugation of a regular verb such as trinken, showing the regular endings.
They also talk about vowel change in some verbs, say that this only happens in the du and er/sie/es forms, and give the example du isst, er isst below the table.
This should be enough for you to derive the complete conjugation of the verb essen.
The verb conjugation of essen in particular will also be shown later in the tips and notes for the unit "Animals 1": https://www.duolingo.com/skill/de/Animals-1/tips-and-notes
Please always read the tips and notes before starting a new unit.
On the website https://www.duolingo.com/ , they are available by clicking on the lightbulb icon after selecting a unit:
They are not available (for most users) in the mobile apps for the German course.
I wish they were, but for now, you will have to use the website to read them.
- ich esse
- du isst
- er / sie / es isst
- wir essen
- ihr esst
- sie essen
So you use isst when the subject is du (you -- one person) or er (he) or sie (she) or es (it) or a singular noun (which could be replaced by "he", "she", or "it").
For example, der Mann isst -- but not die Männer isst (the men is eating) because "the men" can't be replaced by "he/she/it"; "the men" is "they" and so it's die Männer essen (the men are eating) like sie essen (they are eating).
Why is it "Das Mädchen isst einen Apfel" and not "Das Mädchen esst einen Apfel"?
Some verbs change the vowel of their stem, from e to i or ie, from a to ä, or from au to äu, in the du and the er, sie, es forms.
essen is one of them:
- ich esse
- er, sie, es
- wir essen
- ihr esst
- sie essen
Whether a verb does this or not is something that simply has to be learned -- for example, geben has du gibst but leben has du lebst; kaufen has du kaufst but laufen has du läufst.