Long vowels can be formed in three ways:
- double vowel: two identical vowels in a row
- single open vowel: a single vowel at the end of a syllable
- vowel combination: two different vowels in a row that merge into (more or less) one vowel
With the exception of y, each vowel has a short and a long form:
short | a [ɑ] | e [ɛ] | i [ɪ] | o [ɔ] | u [ʏ]
long | aa [a] | ee [e] | ie [i] | oo [o] | uu [y]
Note that long _i_ is not formed by doubling the vowel, but by adding the letter e: _ie._
Long and short vowels