When we are talking about two or more people or objects of the same type, we use the plural form.

Singular: Das ist ein Stift. Der Stift kostet 1,50 Euro.

Plural: Das sind fünf Stifte. Die Stifte kosten 7,50 Euro.

In German there are different ways to form the plural. It is hard to find general rules that are valid in all cases and to say which nouns have which plural endings – and it is even harder to remember these rules and apply them. The best thing is to learn each noun with the definite article and the plural. You can find this information in a dictionary. Usually the plural is not given as a whole word, just as an ending.

Plural example: the masculine word "Stift" forms its plural "Stift" by adding "-e" at the end. — null DW

The plural of Stift is formed with the ending -e, becoming: die Stifte.

Plural example: The neuter noun "book" forms its plural "Bücher" by adding "-er" at the end and changing the "u" to "ü". — null DW

The plural of Buch is formed with an umlaut (the symbol for this is a dash with two dots above it, as you see in the picture above) and the ending -er, becoming: die Bücher.

There are five different plural endings:

Ending	Example
-n	die Brille, die Brillen
-en	die Zahl, die Zahlen
-e	der Stift, die Stifte
-er	das Kind, die Kinder
-s	das Foto, die Fotos

Some nouns have no different ending.

Example:

der Lehrer, die Lehrer

Some nouns also gain an umlaut on one of the vowels in the word in the plural.

Examples:

der Notizblock, die Notizblöcke

das Buch, die Bücher

der Flughafen, die Flughäfen

Some words have two possible plural forms.

Example: die Pizza, die Pizzen/die Pizzas.

Both plural forms are right and have the same meaning.

Grammatical terms in German:

der Singular: The singular is used when we are referring to a single person or object.

der Plural: The plural is used when we are referring to several people or objects.