That's perfectly right. Moreover, there are two letters for "V" (bet and vav), two letters for "K" (kaf and kof) and for "S" (samekh and sin). The sound of ALEF disappeared (originally that was a glottal stop), and the sound of AIN mostly remains in speech of Israeli Arabs. Therefore the modern Hebrew abounds in vocalic vowel combinations where originally glottal consonants presented (like ME-OD, SHA-A etc.).