For more than a century of the Chinese language research history, linguists have been scrutinizing grammatical properties (syntactic patterns) of functional words. Meanwhile, there is a high demand to study their behavior and frequency of occurrence in various contexts and genres. This article examines two functional words of modern Chinese – 因为 yīnwèi 'because (of)' and 由于 yóuyú 'because (of)' – denoting causal relations. The aim was to identify their functioning patterns as conjunctions and homonymous prepositions in various contexts and to 164 determine the frequency of their occurrence in each function depending on a speech genre. During the study, descriptive and comparative methods were applied together with context analysis (based on semantic and stylistic features), descriptive statistics was also used. Among the genres, journalistic texts, fiction and spontaneous speech were chosen. The total of 900 contexts for each of the two words were analyzed. It was found that the frequency of occurrence of these functional words directly depended on the genre. Both words had similar number of occurrences in journalistic texts, however in fiction the ratio was 78% to 22% respectively, and in spontaneous speech the gap was even wider – 97% to 3%. In most cases, 由于 was used as the homophonepreposition while 因为 was used as the homophoneconjunction.
Cherednichenko et al. (2023) studied this question.