Definition - A sentence is a group of words that includes a finite verb. Sentences are made up of phrases and clauses: phrases are groups of words that are used together to express a certain idea; clauses are phrases that contain a verb. In a sentence composed of more than one clause, the main clause is the clause that makes sense on its own; subordinate clauses are other clauses that give additional information, but cannot stand alone.

Examples of German sentences:
             • Ich bin Olga.
                [I am Olga.]
             • Wenn wir mehr Geld haben, kaufen wir ein großes Auto.
                [When we have more money, we will buy a big car.]
             • Renate hat eine weiße Katze, aber sie möchte einen schwarzen Hund.
                [Renate has a white cat, but she would like a black dog.]

Types - This is a short list of different kinds of sentences:

Declarative sentences are statements. These sentences are sometimes referred to as 'positive' sentences to distinguish them from negative sentences. Examples:
             • Das Buch ist billig. [The book is inexpensive.]
             • Ihr geht in den Supermarkt. [You go into the supermarket.]
             • Der Wein ist sehr trocken. [The wine is very dry.]

Negative sentences express a negation:
             • Das ist kein teures Buch. [This is not an expensive book.]
             • Ihr geht nicht in das Hotel. [You do not go into the hotel.]
             • Der Wein ist nicht süß. [The wine is not sweet.]

Interrogative sentences are questions:
             • Kostet das Buch zehn Euro? [Does the book cost ten Euros?]
             • Wohin geht ihr? [Where do you go?]
             • Welcher Wein ist das? [What wine is this?]