the plural in German is "Knöpfe" (alternativ if you need to write the word on a computer without the "ö"-button, than it's written "Knoepfe")
German plural forms are formed irregularly.
The plural of "Apfel" in German is "Äpfel".
The plural form for "German" is "Germans."
The plural for computer is computers.
The noun computer is the singular form; the plural form is computers.
The plural of computer is computersand the plural of is is are, e.g. the computer is expensive: the computers are expensive.
Kugelschreiber is both the singular and plural.
German shephards.
The plural form of the German word Wohnwand is Wohnwände
The plural of Fach is Fächer.
das Poster (singular) die Poster (plural)