1) Some nouns are always plural in English, but singular in German.
eine Brille | glasses, spectacles |
eine Schere | scissors |
eine Hose | trousers |
These nouns used in the plural in German mean more than one pair.
zwei Hosen | two pairs of trousers |
2) To form the plural
SINGULAR | PLURAL | |
no ending | das Messer (knife) | die Messer |
added E | der Schuh (shoe) | die Schuhe |
added (E)N | die Ampel (traffic light) | die Ampeln |
added ER | das Lied (song) | die Lieder |
added S | das Büro (office) | die Büros |
(with umlaut) | der Mantel (coat) | die Mäntel |
(with umlaut) | der Wald (forest) | die Wälder |
(with umlaut) | die Wurst (sausage) | die Würste |
irregular | das Datum (calendar date) | die Daten |
3) Nouns of measurement and quantity
These nouns, used to describe the quantity or size of something, usually remain singular
Möchten Sie zwei Stück? | Would you like two? |
Ich wiege fünfzig Kilo. | I weigh eight stone. |
The substance which they measure follows in the same case as the noun of quantity.
Sie hat drei Tassen Kaffee getrunken. | She drank three cups of coffee. |
Er wollte zwei Kilo Kartoffeln. | He wanted two kilos of potatoes. |
Drei Glas Weißwein, bitte! | Three glasses of white wine, please. |