Spoken English shows great variation across regions where it is the predominant language. For example, the United Kingdom has the largest variation of accents of any country in the world, and therefore no single "British accent" exists. This article provides an overview of the numerous identifiable variations in pronunciation; such distinctions usually derive from the phonetic inventory of local dialects, as well as from broader differences in the Standard English of different primary-speaking populations. Accent is the part of dialect concerning local pronunciation. Vocabulary and grammar are described elsewhere; see the list of dialects of the English language. Secondary English speakers tend to carry over the intonation and phonetics of their mother tongue in English speech. For more details on this, see non-native pronunciations of English. Primary English speakers show great variability in terms of regional accents. Examples such as Pennsylvania Dutch English are easily identified by key characteristics, but others are more obscure or easily confused. Broad regions can possess subforms; for instance, towns located less than from the city of Manchester (such as Bolton, Oldham, Rochdale, and Salford) each have distinct accents, all of which are grouped together under the broader Lancashire accent. These sub-dialects are very similar to each other, but non-local listeners can identify firm differences. On the other side of the spectrum, Australia has a General Australian accent which remains almost unchanged over thousands of miles. English accents can differ enough to create room for misunderstandings. For example, the pronunciation of "pearl" in some variants of Scottish English can sound like the entirely unrelated word "petal" to an American. For a summary of the differences between accents, see the International Phonetic Alphabet chart for English dialects. Overview English dialects differ greatly in their pronunciation of open vowels. In Received Pronunciation, there are four open back vowels, , but in General American there are only three, , and in most dialects of Canadian English only two, . In addition, which words have which vowel varies between dialects. Words like bath and cloth have the vowels in Received Pronunciation, but in General American. The table above shows some of these dialectal differences. Britain and Ireland Accents and dialects vary widely across Great Britain, Ireland and nearby smaller islands. The UK has the most local accents of any English speaking country. As such, a single "British accent" does not exist. However, someone could be said to have an