把下面的内容翻译为英文：学习投入是指学生在学习过程中投入的时间和精力高欣峰等2020是衡量教育质量的重要指标是影响大学生学业成功的重要因素沙景荣等2020；马婧周倩2019；苏琪2019。目前学习投入三维理论居于主导地位即行为投入、认知投入和情感投入。随后 Fredricks 等2016 将其扩展为行为、认知、情感和社交四个维度其中行为投入指学生参与学业和课堂活动的表现包括注意力、参与度、作业完成

Learning engagement refers to the time and effort students invest in the learning process (Gao, et al., 2020). It is an important indicator for measuring educational quality and a crucial factor influencing academic success among college students (Sha, et al., 2020; Ma, Zhou, 2019; Su, 2019). Currently, the dominant theory of learning engagement is the three-dimensional model, which includes behavioral, cognitive, and emotional engagement. Subsequently, Fredricks et al. (2016) expanded it to include a fourth dimension, social engagement. Behavioral engagement refers to students' participation in academic and classroom activities, including attention, involvement, homework completion, and classroom discipline. Cognitive engagement refers to students' self-regulation, perseverance, efforts to understand complex concepts, or master difficult skills. Emotional engagement refers to students' positive emotions towards teachers, classmates, and classroom activities, as well as their psychological states of interest, enjoyment, or identification with school or subjects. Social engagement refers to students' interaction with peers or teachers, the quality of their involvement, and their social behavior in the classroom (Li, 2021). The measurement of learning engagement mainly relies on questionnaires, such as the National Center for School Engagement (NCSE), the National Survey of Student Engagement (NSSE), and the Utrecht Work Engagement Scale-Student (UWES-S) (Gao, 2020). Additionally, understanding students' learning engagement can also be achieved through teaching platform logs, online discussion content and quality, video analysis tools, and offline classroom observations. Searching for "blended learning engagement" and "learning engagement in a blended teaching environment" as keywords in CNKI, only 12 relevant core journals were found. The earliest publication dates back to 2018, while the majority were published in recent years. In conclusion, learning engagement has become a hot topic in research in recent years and has gained significant attention (Han, 2020)