We have addressed two different tenses that you can use to talk about the past in German, the “Präteritum” and the “Perfekt“ (perfect tense). Whereas the “Präteritum” is used for any form of written language (literature, news, letters), the “Perfekt” is used for spoken language. When compared to the English past tenses, the German "Perfekt" is used for both the simple past and the present perfect, so it is like killing two birds two birds with one stone.
The “Perfekt” is either formed with the respective form of “sein” (to be) or “haben” (to have) and the participle II form of the verb. The form of “sein” or “haben” is in the second position whereas the participle form always moves to the last position.
You can form the “Perfekt” with either “sein” or “haben”. There are some rules which will show you which one to use (see table). Verbs that suggest a change of place occur way more often than verbs that suggest a change of state. Special verbs with „sein“ are very rare, as well. Therefore, look out for verbs that have anything to do with walking, driving, flying, etc., these will be formed with „sein“. Note, however, that a "change of place" means a movement from A to B (direction). When playing football, you will change your place as well, but not purposefully or target-orientated, which is why we would use "haben" instead of "sein" with "spielen" (to play).
In fact, we often use the Present Tense in German to talk about the future, as well. Take the following example, "Morgen gehen wir ins Kino" - "Tomorrow we'll go to the cinema". So you can do a lot with this tense!
The most important thing about the German perfect tense when it comes to sentence structure is that the participle form moves to the end of the sentence. Between the verb forms (second and last position) can be pretty much everything, a direct object, an indirect object, or an adverbial phrase of time or place.
▪ The subject (Nominativ) is in first position
▪ The form of "sein" or "haben" is in second position and participle is in last position, separable verbs do not split up
▪ The objects are placed in between the respective form of "sein" or "haben" and the participle. When there are both objects, the indirect object usually precedes the direct object
▪ Questions are formed as usual, finite verb ("sein" or "haben") and subject change each other's place
▪ When it comes to negation, "nicht" is put after "sein" or "haben" in third position
We use the Akkusativ after almost every verb ("Ich habe einen Bruder"), the only exception is "sein", as this verb equates the following noun with the subject and we therefore have to use the Nominativ ("Tom ist mein Bruder").