is there a predictable correspondence between word sound and word spelling
Besides the quirks the English spelling system has inherited from its past, there are other idiosyncrasies in spelling that make it tricky to learn. English contains, depending on dialect, 24--27 separate consonant phonemes and 13--20 vowels. However, there are only 26 letters in the modern English alphabet, so there is not a one-to-one correspondence between letters and sounds. Many sounds are spelled using different letters or multiple letters, and for those words whose pronunciation is predictable from the spelling, the sounds denoted by the letters depend on the surrounding letters. For example, the digraph th represents two different sounds (the voiced dental fricative and the voiceless dental fricative) (see Pronunciation of English th), and the voiceless alveolar sibilant can be represented by the letters s and c.
English orthography