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Usage - Gebrauch

The German definite article, in short, replaces the word "the" in English, with just a few suggestions. Formally, it is used for

• something which already has been mentioned or is already known. Readers or listeners know what someone is writing or speaking about. For example, "Ich habe eine Tasse. Mit der Tasse kann ich trinken."
• something that there is only one of (nouns of rivers, mountains, stars, planets): die Alpen, die Donau
• the superlative: das ist der höchste Berg der Region)
• generalizations (X is a kind of....): Die Rose ist eine Blume.
• certain countries and regions: die Schweiz, die Türkei, die USA (plural), das Elsass, die Steiermark
• abstract concepts, such as das Glück and das Leben -- this use differs from English.