The most common syllable patterns center on a vowel sound as either a closed or open syllable. Closed syllables are short vowels (V) surrounded by consonants (C). The word "cat" has the pattern CVC (consonant/vowel/consonant). Open syllables are long vowel sounds where the vowel can stand alone. The two syllable word "cater" is divided as a CV-C pattern. The long "a" does not need a consonant after it, so the "t" in the word is detached from the first vowel and becomes the first sound of the next syllable.
Syllable patterns differ depending on how many consonants are between the vowels. Another common pattern used to divide multisyllable words is the VCCV pattern. When two consonants separate vowels, split the syllable between the consonants. The word "button" would be divided as but-ton (CVC-CVC). Many words contain consonant combinations called blends and digraphs. In these cases, the consonants will remain together, as they are considered to be one sound. The word "construct" would be divided as con-struct (CVC-CCCVCC). The "str" is a blend and stays together. The word "perchance" would be divided as per-chance (CVC-CCVCC). The "ch" is a digraph that forms one sound.
Not all vowels make syllables, and some consonants can substitute as vowels. Silent vowels, "e" being the most common, are never counted in syllables as a sound. Vowel combinations can produce either a voiced or an unvoiced vowel, such as in the word "read" where the "a" is silent, or they can produce a new sound, called diphthongs. These count as one vowel sound, such as in the word "cause." Consonants "y" and "w" can also be used as vowel sounds, such as in the words "bunny" and "tow." Double vowels can also have different sounds and therefore need syllable splitting, such as in the word "radio."
Syllable patterns for add-ons like prefixes and suffixes follow the same rule used for compound words. In a compound word, syllables are divided between the words. Thus the word "wishbone" would be divided as wish-bone. Prefixes and suffixes are considered to be self-contained word chunks already, so they stay together when attached to another word. Thus the word "ungrateful" would be divided as un-grate-ful.