As English-medium instruction (EMI) spreads around the world, university teachers and students who are non-native speakers of English (NNS) need to put much effort into the delivery or reception of content. Construction of scientific meaning in the process of learning is already complex when instruction is delivered in the first language of the teachers and students, and may become even more challenging in a second language, because science education depends greatly on language. In order to identify important pedagogical functions that teachers use to deliver content and to present different ways to realise each function, a corpus of lectures related to science and engineering courses was created and analysed. NNS teachers and students in science and engineering involved in EMI higher education can obtain insights for delivering and listening to lectures from the Online Corpus of Academic Lectures (OnCAL).