Most phonology textbooks claim that the phonological system of the English language is composed of 44 phonemes, of which 24 are consonants (actually, two are semivowels) and 20 are vowels. Yet, this number results of a misinterpretation of the English vowel system, since several authors consider clusters of sounds (diphthongs and pseudo triphthongs) as single phonemes, as well as combinatorial allophones of the same phoneme as distinct phonemes. By employing the definitions of phoneme, phone, and allophone, together with the criteria of commutation and substitution formulated by Trubetzkoy and the phonologists of the Prague School, allied to the concept of neutralisation and archiphoneme of the traditional structural phonology, it is possible to prove that the real number of phonemes of English is actually 35. This paper intends to revise the English phonological system, especially regarding vowels, by using the same methodology employed to describe the phonology of other languages, such as French, for example. As a result, we will try to demonstrate that the current phonological description of the English language has a lot of idiosyncratic and, therefore, a new view of this system will reflect on the phonemic transcription of words made by dictionaries, making it simpler.