Tips de transcripción fonética en inglés

Transcription Tips
Here are a couple of tips for students who are learning how to write broad phonemic transcription of English. As well as give positive suggestions, these will draw your attentionto a number of pitfalls to be avoided:
* First of all, use a coherent set of symbols, obviously that used by your lecturer and make sure that your dictionary uses the same set (phonetic symbolsare usually listed at the start of dictionaries). There is a rather large difference between the American and British schools in this sense, and even British material varies according to its date. Theset that I recommend and use is that used by such authors as John Wells and Peter Roach in their respective Pronouncing Dictionaries.
Some of the characters in the set will be new to you: observe themcarefully and practice writing them. Some of the main pitfalls are below:
* Remember that the tops of the /ʊ/ symbol point outwards, make sure you are distinguishing it from /u/ 
* The schwa,/ə/, is an 'e' that has been rotated 180?, make sure it will not be confused with /a/
* Remember that there is an important distinction between /a/ and /ɑ/, the first is a front and the second aback vowel. Diphthongs use the former e.g. /aɪ/, /aʊ/
* Similarly, English diphthongs use /ɪ/ rather than /i/, e.g. /aɪ/, /ɪə/, /eɪ/, and /ʊ/ rather than /u/ e.g. /əʊ/, /aʊ/, /ʊə/
* The /ʃ/symbol is a stretched 's', it reaches from the height of the top of a capital letter to the bottom of a 'p', for example. 
Also:
* Remember to use /k/ instead of 'c' for the voiceless velar stopand /j/ rather than 'y' for the palatal approximant
* Orthographic 'x' is usually transcribed as /ks/, e.g. 'fax' => /fæks/. The phonetic symbol [x] does exist but it is rarely used in English(only for foreign words).
* An orthographic 'n' before a velar, i.e. /k/ or /g/ should be transcribed as a velar nasal stop with the /ŋ/ symbol, e.g. 'thanks' => /θæŋks/
* Remember to put...