Abstract: In recent years, with the development of study on worked-example learning, various taxonomies of worked-examples have appeared. The distinction of single-content examples and double-content examples was one of these classifications. This paper presents an overview of recent researches on double-content example learning. The review introduces the comparisons between single-content examples and double-content examples and the relationship between two levels of double-content examples, which indicates the essential features of double-content examples. In addition, this paper also summaries the empirical researches on double-content example learning during these years. Researchers have conducted a series of studies in different fields, including knowledge learning, skill acquisition and strategy acquisition, which demonstrated the positive effects of double-content example learning. Firstly, many researchers did researches on the effect of double-content examples in knowledge learning, especially, the impact of completion of examples, feedback and cooperative learning in double-content examples learning effect. Secondly, double-content examples were also applied in skill acquisition, such as negotiation skill, spreadsheet applications in learning mathematics, cooperative learning skill, argumentation skills, and selection and design worked-out examples for high school students. Lastly, researchers explored the effects of double-content examples in learning strategy acquisition, involving concept mapping, learning journal, and so on. Based on the literature of different researches, this paper provides five important implications. The first one is the distinction between single-content examples and double-content examples. In double-content examples, both the learning domain and exemplifying domain should be new knowledge to learners. Therefore, future researches should aim to explore the learning effect of different double-content examples based on the combination of familiarity in learning domain and exemplifying domain. Secondly, double-content examples extended the presenting format and learning function of worked-out examples. Different from traditional worked examples, new formats like video, image and written composition were employed in double-content examples. This change further expands the traditional applied fields of mathematics and physics to fields like medical care, psychological diagnosis and treatment, instructional design, learning strategy, communication skills, cooperative learning skill, and argumentation skills. Thirdly, researchers need to pay more attention to the comparison of the learning effect of single-content example and double-content example. According to Cognitive Load Theory, single-content examples are obviously better than double-content examples in learning effect, because the latter ones involve cognitive processes in two levels. However, double-content examples are superior to single-content examples in the application effects. Hence, researchers should take full advantage of the two different example types through optimal combination. Fourthly, the evaluation of the learning effect of double-content examples is a problem to be considered. Currently, researchers haven’t come to an agreement on the evaluation criterion of double-content example learning. This paper suggested that researchers should examine the interaction of both level, that is, learning domain and exemplifying domain, as well as the measurement of cognitive load. Lastly, three cognitive processing models of double-content example learning are proposed in theory to describe and explain the cognitive process of double-content example learning, which are sequential processing-integrated model, parallel processing-integrated model and interactive processing-integrated model. However, more empirical researches still need to be done in this field to testify which model is correct.

Key words: double-content example, learning domain, exemplifying domain, cognitive processing model

摘要： 文章介绍了单内容样例与双内容样例的划分标准以及双内容样例在知识学习、技能和策略习得中应用研究的进展。作者从中获得启示，提出了根据学习域和示例域知识的熟悉程度组合不同学习难度的双内容样例并考察其学习效果、比较单内容与双内容样例学习效果的实验模式，并提出了双内容样例学习的三种认知加工模式。

关键词: 双内容样例 学习域 示例域 认知加工模型