A vowel is a usually fully sonorant spoken sound segment that is articulated with an
open glottis. In addition, a full vowel is syllabic; in other words, it represents the nucleus of a syllable. A semi-vowel is an accompanying vowel that by itself can not carry a syllable. A diphthong is a sequence of two vowels immediately adjacent to each other in which one
is a full vowel and the other is a semi-vowel.
There is one important orthographic principle you must remember, a feature
that Low Saxon shares with the Low Franconian languages.
A long vowel is written as a double vowel letter in a closed syllable;
e.g. laat ‘late’, groot ‘great’
A long vowel is written as a single vowel letter in an
open syllable;
e.g. (laa-ter =) later ‘later’, (groo-te =)
grote ‘great (…s)’
This principle applies in most German-based spelling methods as well (with
the official exception of the religious Loccum Guidelines), although use of
lengthening “h” disrupts this system in German-based systems.
