All the syllables ARE pronounced: e- cri-vez Three syllables.

EZ is a syllabe, prounonce it like a "er" in the word "AIMER" ou "é" de "aimé". it's the same pronounciation for the three forme (ez, er, é) but the "ez" form that is specific of the use of the second person of plurial. When you read "ez" in a verb, it's when you use the "VOUS" , the "you" polite, or "you" when they are more than one person. when you use the "VOUS", pronounce [e] like in the verb "aimer" (love in english), but whrite it whith EZ . http://fr.wikipedia.org/wiki/Voyelle_mi-ferm%C3%A9e_ant%C3%A9rieure_non_arrondie PS, there are some words in EZ that aren't verb, like "rez-de-chaussée" (groud-floor), nez (nose) , and maybe others that i don't remember

I think the answer is that it's the general rule of reading French. Letters "e, s, t, d, x, p, g, z" are not pronounced, if they are at the end of the sentence. P.S. there are other rules, try to find them ;)

You meant to ask "why aren't all the syllables pronounced?". I am not a French "expert", but I hear all of the syllables when I say the word. The letters combine to form the sounds of the syllable. For example, the "vez" makes a clear, defined sound.