Learn How to Use In, An or Auf Correctly in German

Although German is a straightforward language once you learn the rules, you can't always directly translate every word from English. In fact, the more you study some words, the more confusing they may become. Three German prepositions, in particular, can be tricky for beginners: in, an and auf. 

What Is a Preposition?

A preposition is a word that is typically paired with a noun (or pronoun, like he or she) that helps you understand that word's relationship to another part of the sentence. For example, prepositions can refer to the noun's position in space or time. Like "put your feet under the table," or "go shopping after class."

But many English prepositions have different meanings. "Under" can be below, but it can also mean less than. Some prepositions are colloquial or you just have to memorize them, like "get down with." 

The same goes for German. You can memorize the meanings of the prepositions, but not all will be a direct translation of the English counterpart. 

These are all two-way prepositions, meaning the noun/pronoun that follows this preposition will be conjugated in the accusative (if it is used to express motion/action, like "I walk into the store") or dative (if it is used to express a location or position, like "I stand in the street"). In English, the preposition does not change the noun/pronoun it precedes. 

In

Means: in, into, to

Examples: Ich stehe in der Straße. (I stand in the street.)

Die Frau ist in der Universität. (The woman is in the university, as in she is physically inside the university building. If you want to say you are enrolled in the university, you say, " an der Universität," as in "at the university." See below.) 

An

Means: at, to, up next to 

Examples: Ich sitze an dem Tisch. (I am sitting at the table.)

Die Frau ist an der Tankstelle. (The woman is at the gas station, as in she is literally standing up next to the vertical gas pump. It can be helpful to think about a side-by-side, vertical encounter to remember when to use "an" as in "up next to.") 

Auf

Means: on, on top of

Examples: Die Backerei ist auf der Hauptstraße. (The bakery is on the main street.)

Die Frau ist auf der Bank. (The woman is on the bench, as in she is literally sitting on top of the horizontal bench. A horizontal encounter is often key for "auf.") 

Other Considerations 

Some verbs come standard with a preposition. Think about "hang out" or "hang up" in English; the preposition is an important component of the verb that actually changes the meaning of it.