“是”字句是对外汉语教学中的一种重要句型,汉语作为第二语言的学习者在日常的口语交际和书面表达中使用频率较高。然而,由于汉语和英语语言在语法结构、语义表达等方面的差异,使得留学生在学习“是”字句时常常出现偏误。论文以对比语言学理论为指导,以HSK动态作文语料库为基础,结合对比研究和语料研究的方法,分析归纳英国、加拿大、美国等7个母语为英语背景的留学生在学习“是”字句时的偏误类型和原因,并提出针对性的教学策略和建议,以期为汉语作为第二语言的教与学提供理论和实践指导,丰富和深化相关研究。The “是” sentence is an important sentence pattern in the teaching of Chinese as a foreign language, and learners of Chinese as a second language use it more frequently in their daily oral communication and written expression. However, due to the differences between Chinese and English in terms of grammatical structure and semantic expression, international students often make mistakes when learning “是”-sentences. Based on the theory of comparative linguistics and the HSK Dynamic Composition Corpus, the thesis analyzes and summarizes the types and causes of the errors in learning “是”-sentences of seven international students from the UK, Canada and the US with native English backgrounds by combining comparative and corpus research methods, and puts forward targeted teaching strategies and suggestions with a view to The study provides theoretical and practical guidance for the teaching and learning of Chinese as a second language, and enriches and deepens related research.