2. The method of claim 1 , further including: using results of the similarity tests to map at least part of the second language phonemes to sets of phonemes of the first language by: assigning respective scores to results of the similarity tests; and mapping one or more of the second language phonemes to a set of mapping phonemes of the first language, the set of mapping phonemes being selected from the candidate mapping phonemes as a function of the scores; and including the first language sets of phonemes resulting from the mapping in a stream of phonemes of the first language representative of the text to produce a resulting stream of phonemes that are used to generate a speech signal.
3. The method of claim 2 , wherein the phoneme of the second language, which is mapped to a set of mapping phonemes of the first language, is selected from: a set of phonemes of the first language including three, two, or one phonemes of the first language, or an empty set, whereby no phoneme is included in the resulting stream for the phoneme in the second language.