<bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Background:</b> Zhihu live talks, as a major online knowledge commodity, enable speakers to provide professional information and interact with the audiences. The use of hedges and boosters has been associated with the realization of such a goal. <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Literature review:</b> Previous research has indicated the relevance of disciplines or genres in the use of hedges and boosters in academic discourse; however, little is known about the use of these metadiscourse markers in Zhihu live talks as a new register for popularizing professional knowledge. <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Research questions:</b> 1. What are the disciplinary variations in the use of hedges and boosters in medical science and health (Med) and education (Edu) live talks? 2. To what extent do speakers’ characteristics (i.e., expertise and community status) have an impact on the use of hedges and boosters in Med and Edu live talks? <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Research methods:</b> We collected the transcripts of 123 Med and 126 Edu live talks, as well as the demographic information of each speaker. Following a framework adapted from Hu and Cao, we conducted an analysis of the frequencies and functions of hedges and boosters, and how they associate with speaker characteristics in each category of live talks. <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Results:</b> The two corpora exhibited significant differences in the frequencies and functions of hedges/boosters, and the differences can be attributed to the conventions of knowledge making in medicine and education disciplines. In addition, speaker characteristics have some impact on the use of hedges and boosters, such as speakers’ levels of conformity to disciplinary conventions or their strategic efforts in relational management. <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Conclusion:</b> The findings can guide different speakers to configure metadiscourse to inform, argue, and direct while popularizing professional knowledge of different disciplines.

Background: Corporate social responsibility (CSR) reports are one of the vehicles for developing corporate images, namely, the cognitive representation of a company perceived by the concerned stakeholders. It would be interesting to compare the CSR reports of companies of the world's two largest economies: the US and China. Literature review: Previous studies of CSR reports tend to highlight their lexicogrammatical, semantic, and functional features at the discursive level, but few studies have examined the cognitive images that companies intend to develop at the level of conceptual structure (knowledge representation). This study investigates metaphor use as a discursive and cognitive strategy for developing corporate images in Chinese and American CSR reports from the perspective of corpus-based conceptual metaphor analysis, particularly based on the concept of genre-specific metaphors, the metaphors used to conventionally construe notions for a certain communicative purpose achieved by a particular discourse community. Research questions: 1. What are the major concerns of Chinese and American CSR reports? 2. What are the genre-specific metaphors used to construe major concerns of Chinese and American CSR reports? 3. What do the genre-specific metaphors reveal about the corporate images of Chinese and US companies? Are there differences in developing corporate images between Chinese and American CSR reports? Methodology: We collected CSR reports of the top companies in China and the US, identified genre-specific linguistic and conceptual metaphors, and conducted comparative analysis of metaphor-based corporate images. Results and conclusions: The conceptual metaphors genre-specific to CSR reports are businesses are objects, business is war, business is a journey, and business competition is competitive games/sports. Furthermore, CSR reports of both countries share most genre-specific metaphor parings and thus nearly the same mappings, which contribute to building corporate images of being economically competitive, ethically cooperative, and environmentally responsible. Although both stress self-development and taking a leading position, American companies seem to pay more attention to external cooperation with others. On the other hand, Chinese companies seem to stress internal cooperation and a well-organized hierarchy. Admittedly, this study may be limited in terms of analyzing only genre-specific metaphors and not balancing sector types of the companies in the two corpora.