EN
This article draws on data obtained through research on pronunciation among Czech speakers in the two most populous cities in the Czech Republic (Prague, Brno, 2014). Fluctuation in vowel length (vowel quantity) was observed in 240 of 300 researched expressions of foreign origin. The vowel quantity fluctuates particularly in word endings (e.g. -on: balon ‘ball’, citron ‘lemon’; -ura: literatura ‘literature’, procedura ‘procedure’). But because it does not fulfil a particular function, it does not prevent the spoken words from being understood. When comparing our results with those from studies conducted in the second half of the 20th century, we observed a growing tendency in Czech to shorten the vowels in loanwords (for instance, the word endings -iv, -ivní). However, this trend is not observable everywhere; for instance, the ending -in continues to be pronounced in its longer form (in 90 % of cases), although a wider range of shorter versions was expected here as well. There are also quite contradictory tendencies, for instance the word kontejner ‘container’ or evangelium ‘gospel’ do not have long forms in the dictionaries, but the research reveals that long vowels are often pronounced. The results also suggest that in many expressions the vowel length in Czech is influenced especially by the age of the respondents.