研究表明，通过观看视听材料（例如电视节目）可能习得外语词汇，但习得词汇的数量通常较小。研究也发现，在视频中添加各种类型的字幕（尤其是一语和二语字幕），相较于不添加字幕，更有助于词汇习得。然而，针对不同字幕对词汇习得的不同影响效果，研究结论仍不一致。过往研究对于相对较新、正在兴起的二语字幕的关注也还不够。相关研究也鲜少聚焦中国高中英语学习者，尽管《普通高中英语课程标准（2017年版）》（中华人民共和国教育部，2018）已经将“看”作为新的重要语言技能提出，同样提出的还有 “多模态语篇”和“视听输入”等新理念。

本研究复制了Peters、Heynen和Puimège (2016)研究中的实验一，但研究对象改为中国的高中英语学习者。除了原研究中涉及的一语和二语字幕，本研究还将如今兴起但研究得较少的一种字幕，即双语字幕，加入对比。出于可行性与因地制宜的考虑，还更改了前词汇知识测试的工具（改为Webb、 Sasao和Balance在2017年发表的新词汇层级测试）和测试提示词的格式（改为书面形式）。同时，为了检验结论适用性并寻求对结果更详细的解释，还扩大了目标词汇数量。为更好地理解学习过程和实验结果，还主要参考了Peters和Webb (2018)所使用的问卷，收集了其他量性和质性的数据。

本实验中，三组高中学生（共90人）首先进行了前词汇知识测试和针对目标词词形、词义的前测。一周后，每组学生观看了同一部英语视频，但字幕条件分别为一语、二语和双语字幕。其后，立即进行了目标词后测与问卷调查，部分学生回答了一些额外的问题。

部分研究结果与复制研究相似。总体上，在词义习得方面双语字幕相比二语字幕具有压倒性优势，在词形习得方面二语字幕相比一语字幕优势明显。一语和二语字幕在词义习得、二语和双语字幕在词形习得方面的差异似不显著。同时，目标词在视频中出现的次数以及学习者的前词汇知识与词汇习得积极相关，且有时两者之间或者同字幕类型之间具有交互作用。目标词的选择对结果有潜在影响。本研究对于教师、学习者、教材编写者、视频平台等具有启示。

Research has shown that vocabulary acquisition through viewing audiovisual materials (such as TV programs) is possible, yet the amount of words learnt tends to be small. It is also found that different types of subtitles (especially L1 and L2 subtitles), which are often added to the audiovisual materials, are potentially conducive to better word learning, as compared to viewing with no subtitles provided. However, research results are inconclusive as to the differential effects of different types of subtitles on word learning. It can also be seen from literature that bilingual subtitles as a relatively new and thriving type of subtitles have not received due attention. Relevant studies also seldom focus on Chinese high school EFL learners, yet New English Curriculum Standards (Ministry of Education of People’s Republic of China, 2018) has already put forward Viewing as the new important language skill, along with the new notions of Multimodal Discourse and Audiovisual Input.

This study aims to replicate Experiment One of the comparative study conducted by Peters, Heynen and Puimège (2016), with a different population (i.e., Chinese high school EFL learners). Apart from the two types of subtitles (L1 and L2) in the original study, another thriving but less studied type of subtitles (the bilingual subtitles), was added to comparison. For feasibility issues and to better suit the Chinese context, changes were also made regarding the test of prior vocabulary knowledge (the new Vocabulary Levels Test by Webb, Sasao & Balance, 2017) and the format of test prompts (in written form). The group of target word items was also extended to examine applicability and to seek detailed explanation of the results. To better understand the learning process and the results, other quantitative and qualitative data were also collected, mainly with reference to the questionnaire used by Peters and Webb (2018).

In the experiment, three groups of students (N=90) first took a prior vocabulary test and target word form recognition and meaning recall pre-tests. One week later, each group watched an English video with one type of subtitles (L1, L2 or bilingual), which was followed immediately by target word posttests and a questionnaire. Some students were asked extra questions.

Findings partly confirmed those of the replicated study. In general, bilingual subtitles had overwhelming advantage over L2 subtitles in terms of assisting word meaning acquisition, and L2 subtitles had advantage over L1 subtitles regarding form acquisition. The differences between the power of L1 and L2 subtitles in assisting meaning acquisition, and between the power of bilingual and L2 subtitles in assisting form acquisition, were insignificant. Meanwhile, target word’s frequency of occurrence in the input and learner’s prior vocabulary knowledge were positively related with word learning, and they might interact with each other or with the subtitles condition. The choice of target words might influence the results. Implications are then discussed, mainly for teachers, learners, textbook writers and streaming platforms.