Plurals with trema (-eeën, -iën)

Keeping Vowels Apart

When Dutch nouns are made plural by adding -en, consecutive vowels can sometimes blend together and confuse the pronunciation. To fix this, Dutch uses a trema (two dots over a vowel, like ë) to clearly mark where a new syllable starts.

Nouns Ending in Stressed -ie

Many abstract concepts and academic terms end in -ie with the stress on the final syllable (like de theorie or de analogie). To make these plural, add -ën. This creates the ending -ieën.

During the session we brainstorm about new theories.
Tijdens de sessie brainstormen we over nieuwe theorieën.
Those analogies, we evaluate them tomorrow.
Die analogieën, die evalueren we morgen.

Nouns Ending in -ee

The spelling rule is exactly the same for nouns ending in -ee (like het idee, meaning "the idea"). Just add -ën to form the plural ending -eeën.

We evaluate each other's ideas, as the teacher wants.
We evalueren elkaars ideeën, zoals de docent wil.

This same stressed -ie rule continues to apply to many words you might use when evaluating concepts or holding a session, such as de filosofie and de fantasie.

Her philosophies stimulate the imagination.
Haar filosofieën prikkelen de fantasie.

Nouns Ending in Unstressed -ie

If a noun ends in -ie but the stress falls on an earlier syllable (like de kolonie or de porie), the spelling rule changes. You do not add an extra 'e'. Instead, just add an -n and place the trema over the existing 'e', resulting in the ending -iën.

We build colonies so that we survive.
We bouwen koloniën zodat we overleven.
The doctor shares his insights about our pores.
De arts deelt zijn inzichten over onze poriën.