Some languages have fixed rules of pronunciation. For example, in French, the same letters and syllables are almost invariably pronounced the same way whenever they occur. In English, however, letters can be pronounced in many different ways. For example, there are approximately twenty-five different vowel sounds, which can be conveyed by only five vowels (or six if Y is counted), and the combination 'ough' can be pronounced at least six different ways in most dialects of English, varying up to eight in certain dialects of English.
Pronunciation of some words differs widely according to a person's accent, dialect, and cultural and religious background. This is conveyed in the famous song "Let's Call The Whole Thing Off", from the musical Shall We Dance?, which includes the line: "you say toma[y]to, I say toma[h]to". The 'tomayto' pronunciation of 'tomato' is most common in the America, while the 'tomahto' pronunciation is more common in Britain.
- The number of ways varies according to accent as well as the variety of English, such as American, British, or Australian English. Examples of the different ways are rough, through, bough, cough, dough, thought, though, thorough, and hiccough.