Originally posted by: Kai_E. https://forum.duolingo.com/comment/3751777
Content
Plurals with -en
Plurals with -s
Plurals with -eren
Other plural forms
Forming the plural in Dutch
There are quite a number of ways of forming the Plural in Dutch, so here is an explanation to help you understand exactly how it works.
Plurals with -en
The plural ending -en is the most common plural ending in Dutch. You first get a taste of it in Basics 2 with words like “vrouwen” (“vrouw” in the singular) and “mannen” (“man” in the singular).
If you’ve read the thread about Dutch spelling you now know that a word like “man” becomes “mannen” due to a spelling rule.
This is to be noted when adding the plural ending -en:
de kat (cat) + -en=de katten
de maan (moon) + -en=de manen
de man (man) + -en=de mannen
Other spelling rules, such as f -> v and s -> z, must also be observed:
f ->v
de brief (letter)-> brieven
het bedrijf (company) -> bedrijven
s -> z
de prijs (price) -> prijzen
het huis (house) -> huizen
However, there are some exceptions where these changes don’t occur.
For the following words:
de dans (dance) -> dansen
de kaars (candle) -> kaarsen
de kans (chance) -> kansen
de mens (human) -> mensen
de prins (prince) -> prinsen
de wens (wish) -> wensen
For loanwords ending in -graaf and -soof:
de fotograaf (photographer) -> fotografen
de filosoof (philosopher) -> filosofen
There are also nouns that have a short vowel in the singular get a long vowel after -en is added:
het bad (bath) -> baden
het bedrag (amount) -> bedragen
de dag (day) -> dagen
het dak (roof) -> daken
het gat (hole) -> gaten
In other words, the vowel sound changes.
For these words:
het lid (member) -> leden
het schip (ship) -> schepen
de stad (city) -> steden
And for words ending in -heid:
de mogelijkheid (possibilty) -> mogelijkheden
If a noun ends in -ee or a stressed -ie, a trema is added:
het idee (idea) -> ideeën
de kopie (copy) -> kopieën
Note: If there is no stress on the -ie, the plural is formed by adding an -s ending.
Plurals with -s
There are also a number of nouns that end with -s in the plural, because they either end a certain way or are borrowed words.
The following nouns get the ending -s in the plural:
Nouns with two or more syllables ending on an unstressed -el, -em, -en, -er, -erd, -aar, -aard, and all diminutives:
de tafel (table) -> tafels
het modem (modem) -> modems
de jongen (boy) -> jongens
de vader (father) -> vaders
de stommerd (dummy) -> stommerds
de adelaar (eagle) -> adelaars
de luiaard (sloth) -> luiaards
Most loanwords that end in a consonant, which also end in s in the language of origin:
de film (film/movie) -> films
de computer (computer) -> computers
de roman (novel) -> romans
Nouns ending in an unstressed -ie:
de familie (family) -> families
de organisatie (organization) -> organisaties
Exceptions to this are “de bacterie” (bacteria) -> “bacteriën” and “de porie” (pore) -> “poriën”
The ending ’s (apostrophe s) is added to words ending in -a, -i, -o, -u or -y. This is necessary because otherwise the vowel length would change (think of the spelling rules):
de firma (firm) -> firma’s
de taxi (taxi) -> taxi’s
de auto (car) -> auto’s
de paraplu (umbrella) -> paraplu’s
de baby (baby) -> baby’s
Plurals with -eren
A small number of nouns end in -eren in the plural:
het ei (egg) -> eieren
het kind (child) -> kinderen
het blad (sheet/leaf) -> bladeren (leaves (on a tree)) or bladen (sheets (of paper))
Other plural forms
Here are some other plural forms for some common words:
het album (album) -> albums
de catalogus (catalog) -> catalogi
de crisis (crisis) -> crises
de cursus (course) -> cursussen
de koe (cow) -> koeien
het museum (museum) -> musea (or museums)
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B1 
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