Cases are something that you will meet everywhere in the German language. Basically every type of word can be affected by declension, also numerals and substantivised verbs. Verbs can require Dativ, Akkusativ or both. For example, "antworten" requires Dativ: Ich antworte *ihm*. "sehen" requires Akkusativ: Ich sehe *ihn* "geben" takes two objects, one in Dativ, one in Akkusativ: Ich gebe *ihm* (Dativ) *ein Buch* (Akkusativ). Many verbs require that the objects are connected to the verbs with certain prepositions. If you study German you'll have to learn the case(s) each verb demands. For each verb, you will also have to study the preposition needed to connect the verb to the object. Also those who study English have to learn this, it's not a quirk of German. Something similar can be said for Russian, by the way.

Well, the simplest suggestion that comes to my mind is 'just don't think about it at all!' And here is why: I don't believe that this kind of grammar rule will help you in anyway. Because the native speakers do that right because their exposed to it all their life. And unless you're a student of German studies and aim for the D level, it's not for you. It's for people who are really into linguistics and wanna be an academic in this area. But it will not help you to improve your language skills (aka communication skills. There are studies showing that.) If you really wanna (intellectually) understand why you use in a certain situation this or that you have to understand that there is not THE Dativ but a whole bunch of them. And mortals don't want to go that road. Because like I said and I repeat, it will not improve your communication skills. Here is what you do: In the article she says "...because most of the time it is the only form that exists." I would focus only on that. So, take a text or a German book and read it. Everytime you come across a mich/mir, dich/dir mark it and the verb with colors in the same way as the author did. And let your brain take note of it. When you finish a whole book doing it under the condition that you understand the book. You will probably have no problems with it anymore. Like the native speaker you exposed yourself to it enough. greetings Tobi

Well, nouns and adjectives don’t exist all by themselves, but they play a role in a sentence. In English, this role is determined mainly by word order, and sometimes a preposition, but in German, you have more freedom concerning the word order, as the information about the role within the sentence lies in the case of the noun. The subject of a sentence is always in the nominative case. Anything that belongs to something/someone is in the genitive case. Then you have verbs that take objects. Let’s take this simple example: “I give my sister a book” – or with a different word order: “I give a book to my sister”. In German this translates to: “Ich gebe meiner Schwester (Dativ) ein Buch (Akkusativ)” or in a less common word order: „Ich gebe ein Buch (Akkusativ) meiner Schwester (Dativ)“. In English you need the preposition „to“ to clarify what is given and who is the person the object is given to. In German, this information is in the cases. Now this was an example with two objects. In such cases, the object carrying the English “to” usually translates to a German dative, while the other object requires the accusative. This might be a rule of thumb you want to learn – although there are lots of exceptions to this. Many other verbs carry only one object. Whether this object has to be in the dative or accusative case depends on the verb, and I don’t know of any rule that tells you which one to use. But it’s always the verb that determines which cases have to be used as object(s). Last but not least, you have prepositions. These also require a particular grammatical case for the nouns that follow them. Sometimes they can be used together with different cases, but then the meaning changes with the case that is used. A popular example is: “in” + dative corresponds to the English “in”, while “in” + accusative translates to “into”. The bottom line is: It is the verbs and the prepositions that determine which cases have to be used in a sentence.