Two-Way Prepositions Part 3

Believe it or not, two German accusative/dative prepositions make yet another distinction that English does not! The common prepositions  an  and  auf  can both mean on or at but they differ in how they are applied to surfaces. If an object is on or near a vertical surface (a wall, a chalkboard, etc.), then usually the prepositionan  is used. If a horizontal surface (a tabletop, a floor, etc.) is involved, then  auf  is used to express on or at. Look at the illustrations below... Horizontal and Vertical ON or ATAN  (vertical) and  AUF  (horizontal) AN  Ã‚  VERTICAL -  SENKRECHT  Ã‚  die Wand  Ã¢â‚¬ ¢ the wall​​ An  object  approachinga vertical surface.The accus. phrase an die Wandanswers the question  wohin? An  object  on or atthe wall.  (vertical surface)The dative phrase an der Wandanswers the question  wo?    AUF  Ã‚  HORIZONTAL -  WAAGERECHT  Ã‚  der Tisch  Ã¢â‚¬ ¢ the table​ An  object  approachinga horizontal surface.The accus. phrase auf den Tischanswers the question  wohin? An  object  onthe table.  (horizontal surface)The dative phrase auf dem Tischanswers the question  wo? Now, if youve been paying attention, can you say what the dative prepositional phrase  an dem Tisch  or  am Tisch  means? Unlike  auf dem Tisch,  an dem Tisch  means at or next to the table. If you are sitting at the table, you are  am Tisch. If you are sitting on top of the table, you are  auf dem Tisch! German is being very consistent here. If you are talking about your location in relation to the vertical part of the table (the legs, etc.), then you use  an. If youre talking about your location in relation to the horizontal top of the table, then you use  auf. This logic also applies to expressions like  an der Donau  (on the Danube). The use of  an  refers to being on the edge of the river. If were actually on the Danube (in a boat), then were  auf der Donau. More Examples  (A accus., D dative)Here are some examples of the uses of  an  and  auf: wo?  an der Ecke  D - on/at the cornerwohin?  an die Ecke  A - to the cornerwo?  an der Grenze  D - on/at the borderwohin?  an die Grenze  A - to the borderwo?  am Rhein  D - on the Rhinewohin?  an den Rhein  A - to the Rhinewo?  auf dem Dach  D - on the roofwohin?  auf das Dach  A - onto the roof Idiomatic ExpressionsBesides their normal uses,  an  and  auf  are also used in many idiomatic expressions and verbal phrases. Here are some examples: auf der Bank  - at the bankjemandem auf der Tasche liegen  - to live off of someoneauf der Straße liegen  A - to be down and outjemanden an der Nase herumfà ¼hren  - to lead someone around by the nose, take them for a foolworan liegt das?  - whats the reason for that? Most of the other two-way prepositions are used in idiomatic expressions as well. Related Links The Four German CasesA guide to the four German cases: Accusative, Dative, Genitive and Nominative. Includes cases and the  two-way  prepositions. A guide to the many ways to say by in German. Prepositional PitfallsPotential problems and how to avoid them.