The progress of speech density – the relationship between the total number of UIRs produced and the total number of turns of phrase accumulated by the group – is also very clear. The students in group A obtained an average density of 39% (54% if we add UIRs in Spanish); in other words, they needed two to three turns of phrase to supply full relevant information. In group B, density is 54% (67% adding in Spanish UIRs) or, in other words, they needed more than one turn of phrase to provide full information. Finally, group C’s speech density approaches 100%, i.e. every turn of phrase provides, on average, a piece of relevant information [see figure 2].

Speech autonomy also shows a clear improvement. The number of turns of phrase containing three or more linked UIRs increases from 24 in group A to 64 in group B and finally 147 in group C [see figure 3].

This progress in speech output is also apparent in subject development and in the appearance of qualitative speech elements (expansion on a theme, contribution of details or stories, etc.), so that we can see a noticeable improvement in the students’ speech proficiency, in accordance with the time elapsed since their arrival in Catalonia [see figure 4].

These differences are particularly noticeable in the conversational exercises, the explanation of festivals and the dilemma situation. The explanation of a television programme or film, in particular or, to a lesser degree, the rules of a game confirm the hypothesis that these have a slightly higher degree of difficulty for all students.