Monosyllabic words can be split into two parts - the onset and the rime - each of which are smaller than syllables, but may be larger than phonemes. The onset is the initial consonant sound (b- in bag, sw- in swim), and the rime is the vowel and the rest of the syllable that follows (-ag in bag, -im in swim). Similar to teaching begining readers about rhyme, teaching children about onset and rime helps them recognize common chunks within words. This can help students decode new words when reading and spell words when writing. The " onset" is the initiial phonological unit of any word (e.g. c in cat) and the term 'rime refers to the string of letters that follow, usually a vowel and final consonants (e.g. at in cat). Not all words have onsets.