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What is the difference between de and het in Dutch?
'Het' is for neuter nouns. 'De' for masculine and feminine nouns.
Although there are some rules, for non-native speakers it more or less comes down to learning 'het' and 'de' words one by one.
Plural nouns = de
Verkleinwoorden/diminutive nouns = het
Noun made from infinitive verb = het
Nouns for persons with identified gender = de (so 'de dochter' (the daughter), but 'het kind' (the child))
Nouns for professions = de
Letters and numbers = de
Nouns for languages = het
Two syllable nouns starting with ge-/be-/ver-/ont- = het
Words ending in -isme/-ment/-sel/-um = het-
Metals = het
Fruits, trees, plants = de- words ending in -ing/-ij/-heid/-nis/-de/-te = de
Words with a foreign origin ending in -ade/-ide/-ode/-ude/-age/-esse/-ica/-iek/-ie/-ine/-iteit/-ose/-sis/-suur/-ys
Words/Names of rivers and mountains = de
Some of these rules have exceptions and there are lots of words that can't be clearly defined by any rule. You'll have to learn them by heart. The best way would probably be regular practice and trying to memorize it as soon as you learn the noun.
There are more 'de' words than 'het' words. Some Dutch learners like to view 'het' words as special words and memorize these. They use 'de' for all the others.
For some words both 'het' and 'de' are fine (like het/de doolhof (the maze)), although this sometimes leads to a different meaning of the word (de/het aas (the ace / the bait)).
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