clearly indicative of its phonemic status (cf. Classical "writer" vs. /mak "written", "eater" vs. "eaten"). In other words, while the glottal stop is predictable in German (inserted only if a stressed syllable would otherwise begin with a vowel), the same sound is a regular consonantal phoneme in Arabic. The status of this consonant in the respective writing systems corresponds to this difference: there is no reflex of the glottal stop in German orthography, but there is a letter in the Arabic alphabet (Hamza (ء)). The writing system of a language may not correspond with the phonological analysis of the language in terms of its handling of (potentially) null onsets. For example, in some languages written in the Latin alphabet, an initial glottal stop is left unwritten (see the German example); on the other hand, some languages written using non-Latin alphabets such as abjads and abugidas have a special zero consonant to represent a null onset. As an example, in Hangul, the alphabet of the Korean language, a null onset is represented with ㅇ at the left or top section of a grapheme, as in "station", pronounced yeok, where the diphthong yeo is the nucleus and k is the coda. Nucleus The nucleus is usually the vowel in the middle of a syllable. Generally, every syllable requires a nucleus (sometimes called the peak), and the minimal syllable consists only of a nucleus, as in the English words "eye" or "owe". The syllable nucleus is usually a vowel, in the form of a monophthong, diphthong, or triphthong, but sometimes is a syllabic consonant. In most Germanic languages, lax vowels can occur only in closed syllables. Therefore, these vowels are also called checked vowels, as opposed to the tense vowels that are called free vowels because they can occur even in open syllables. Consonant nucleus The notion of syllable is challenged by languages that allow long strings of obstruents without any intervening vowel or sonorant. By far the most common syllabic consonants are sonorants like , , , or , as in English bottle, church (in rhotic accents), rhythm, button and lock n key. However, English allows syllabic obstruents in a few para-verbal onomatopoeic utterances such as shh (used to command silence) and psst (used to attract attention). All of these have been analyzed as phonemically syllabic. Obstruent-only syllables also occur phonetically in some prosodic situations when unstressed vowels elide between obstruents, as