mergers before occur in various North American dialects. Mergers of the low back vowels: Other North American mergers that are absent in Received Pronunciation are the merger of the vowels of caught and cot ( and in RP) in many accents, and the merger of father (RP ) and bother (RP ) in almost all. Flat a: Most North American accents lack the so-called trap–bath split found in Southern England: Words like ask, answer, grass, bath, staff, dance are pronounced with the short-a of trap, not with the broad A of father heard in Southern England as well as in most of the Southern hemisphere. (In North America, the vowel of father has merged with that of lot and bother, see above.) However, related to the trap–bath split, North American dialects have a feature known as /æ/ tensing. This results in /æ/ in some environments, particularly nasals to be raised and even diphthongized, typically transcribed as . Thus, answer is typically pronounced as rather than . Flapping of and : In North American English, and both become the alveolar flap after a stressed syllable and between vowels or syllabic consonants, making the words latter and ladder homophones, either as or . The United States does not have a concrete 'standard' accent in the same way that Britain has Received Pronunciation. Nonetheless, a form of speech known to linguists as General American is perceived by many Americans to be "accent-less", meaning a person who speaks in such a manner does not appear to be from anywhere in particular. The region of the United States that most resembles this is the central Midwest, specifically eastern Nebraska (including Omaha and Lincoln), southern and central Iowa (including Des Moines), parts of Missouri, Indiana, Ohio and western Illinois (including Peoria and the Quad Cities, but not the Chicago area). Canada Three major dialect areas can be found in Canada: Western/Central Canada, the Maritimes, and Newfoundland. The phonology of West/Central Canadian English, also called General Canadian, is broadly similar to that of the Western US, except for the following features: The diphthongs and are raised to approximately and before voiceless consonants; thus, for example, the vowel sound of out is different from that of loud . This feature is known as Canadian raising. The is even more raised in Atlantic Canada, closer to . The short a of bat is more open than almost everywhere else