■The_Structure_of_the_English_Syllable An English syllable is composed of the onset and the rhyme (rime). The rhyme itself is composed of a nucleus which is the vowel sound (also called the peak or the centre) and the coda. The onset and the coda are composed of consonant sounds. 1. Some syllables contain only the nucleus (vowel sound) such as: - I /aɪ/ - eye /aɪ/ - are /ɑː/ - a /ə/ - air /eə/ - hour /aʊə/ - our /aʊə/ 2. Some syllables contain an onset a nucleus (vowel sound) such as: - by /baɪ/