This BA thesis investigates the effect of the linguistic interference phenomenon known as ‘false friends’ among Russian-speaking school students who study English as a foreign language. The thesis focuses on one particular type of false friends - partial false friends. The hypothesis of the thesis is: semantic (partial) false friends are the source of negative transfer (direct influence of the mother tongue on the target language) for Russian-speaking learners of English. The thesis consists of two main parts: the theoretical and the empirical part. The theoretical part gives an overview of the main concepts of the field and describes the error and a contrastive analysis used in the thesis.