3. Define and give examples of phonemes, phones and allophones.
Phone - a single basic speech sound, very physical, exactly what we hear. The name `phone` is used for a unit at the phonetic level, it is an unanalyzed sound of a language. It is the smallest identifiable unit found in a stream of speech that is able to be transcribed with an IPA symbol. It is a speech sound or gesture considered a physical event without regard to its place in the phonology of a language; a speech segment that possesses distinct physical or perceptual properties. A phonetic symbol is always set off within [square] brackets. The number of phones is unlimited. (e.g. the word can`t is phonemically /kɑ:nt/ (4 phonemic units) but may be pronounced [kɑ:t] with the nasal consonant phoneme absorbed into the preceding vowel as nasalization (3 phonetic units)
Phoneme - mental, abstract category in which we group phones, an ideal picture, the fundamental unit of phonology, unit of sound. It is the smallest linguistically distinctive unit of sound. Phonemes carry no semantic content themselves. In theoretical terms, phonemes are not the physical segments themselves, but cognitive abstractions or categorizations of them. Each language has a small, relatively fixed set of these sounds. Most phonemes can be put into groups, e.g. in English we can identify a group of plosive phonemes /p t k b d g /, a group of voiceless fricatives / f θ s ʃ h/ and so on.
Allophone - it is one of the several similar speech sounds (phones) that belong to the same phoneme, it is a phoneme in real life. A phoneme is an abstract unit of speech sound that can distinguish words: That is, changing a phoneme in a word can produce another word. Speakers of a particular language perceive a phoneme as a distinctive sound in that language. An allophone is not distinctive, but rather a variant of a phoneme; changing the allophone won't change the meaning of a word, but the result may sound non-native, or be unintelligible. We use the square bracket to indicate phonetic [allophonic] symbols. E.g. in English (BBC) we take it for granted that the /r/ sound in `ray' and `tray' are the same sound (phoneme), but in reality the two sounds are very different: the /r/ in `ray' is voiced and non-fricative while the /r/ sound in `tray' is voiceless and fricative. In phonemic transcription we use the same symbol /r/ for both (slant brackets!) but in phonetic (allophonic) symbols the former is [̻̥ɹ] and the latter [̥ɹ].