a and short e. In West Syriac dialects, and possibly Middle Galilean, the long a became the o sound. The open e and back a are often indicated in writing by the use of the letters א "alaph" (a glottal stop) or ה "he" (like the English h). The close front vowel is the "long" i (like the vowel in "need", ). It has a slightly more open counterpart, the "long" e, as in the final vowel of "café" (). Both of these have shorter counterparts, which tend to be pronounced slightly more open. Thus, the short close e corresponds with the open e in some dialects. The close front vowels usually use the consonant י y as a mater lectionis. The close back vowel is the "long" u (like the vowel in "school", ). It has a more open counterpart, the "long" o, like the vowel in "show" (). There are shorter, and thus more open, counterparts to each of these, with the short close o sometimes corresponding with the long open a. The close back vowels often use the consonant ו w to indicate their quality. Two basic diphthongs exist: an open vowel followed by י y (ay), and an open vowel followed by ו w (aw). These were originally full diphthongs, but many dialects have converted them to e and o respectively. The so-called "emphatic" consonants (see the next section) cause all vowels to become mid-centralised. Consonants The various alphabets used for writing Aramaic languages have twenty-two letters (all of which are consonants). Some of these letters, though, can stand for two or three different sounds (usually a stop and a fricative at the same point of articulation). Aramaic classically uses a series of lightly contrasted plosives and fricatives: Labial set: פּ\פ p/f and בּ\ב b/v, Dental set: תּ\ת t/θ and דּ\ד d/ð, Velar set: כּ\כ k/x and גּ\ג g/ɣ. Each member of a certain pair is written with the same letter of the alphabet in most writing systems (that is, p and f are written with the same letter), and are near allophones. A distinguishing feature of Aramaic phonology (and that of Semitic languages in general) is the presence of "emphatic" consonants. These are consonants that are pronounced with the root of the tongue retracted, with varying degrees of pharyngealization and velarization. Using their alphabetic names, these emphatics are: ח Ḥêṯ, a voiceless pharyngeal fricative, ,