The sequences of adjacent vowels in English like in Romanian language evoke a complex problem that views the quantity and the quality of the phonic elements the hiatus consists of. Pronouncing two vocalic sounds, there can be a pause between them as a result of the reduction of the air current intensity that comes out of the lungs. In this case those two adjacent vowels are separated in two different syllables, producing a vocalic continuity called hiatus. One of the features common to Romanian and English spoken languages through which these two differ from the literary language is the unsteady character of the vowels and the vocalic groups. During a thorough research it came out that in both spoken languages sues a general predisposition of simplifying the act of communication. The given article is a synthesized study of the conditions that favour the phenomenon of the phonic elements’ neutralization, the causes of devocalization, and the ways of hiatus avoidance. The aim of the article is to highlight the common and distinctive features of the vocalic groups of Romanian and English languages in general.