During the COVID-19 pandemic, the use of online instruction through different mobile applications has become more common in education all over the world. Therefore, this research investigated the potential effects of using WeChat-based online instruction on Iranian EFL learners’ vocabulary knowledge. To achieve this objective, 44 Iranian intermediate subjects were picked out among 67 students based on the findings of the Oxford Quick Placement Test (OQPT). The subjects were then randomly divided into two equal groups: experimental and control. After assigning the subjects to two groups, they were pretested by a vocabulary test. Then, the experimental group received vocabulary instruction using WeChat application, while the control group received a conventional vocabulary instruction. After the instruction, a vocabulary posttest was given to both groups to assess the effectiveness of the treatment. The gathered data were analyzed through independent samples t-test, one-way ANCOVA, and paired samples t-test. The outcomes attained in this research demonstrated that there was a significant difference between the posttests of both groups in favor of the experimental group. Eventually, the conclusions and the pedagogical implications of this study were explicated.

中文翻译：

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微信在线教学对英语学习者词汇知识的影响

在 COVID-19 大流行期间，通过不同的移动应用程序使用在线教学在世界各地的教育中变得越来越普遍。因此，本研究调查了使用微信在线教学对伊朗英语学习者词汇知识的潜在影响。为实现这一目标，根据牛津大学快速分班考试 (OQPT) 的结果，从 67 名学生中挑选了 44 门伊朗中级科目。然后将受试者随机分为两组：实验组和对照组。将受试者分为两组后，通过词汇测试对他们进行预测试。然后，实验组接受微信应用的词汇教学，而对照组接受常规词汇教学。指示之后，对两组进行词汇后测以评估治疗的有效性。通过独立样本分析收集的数据t检验、单向 ANCOVA 和配对样本t检验。本研究得出的结果表明，两组的后测之间存在显着差异，有利于实验组。最后，阐述了本研究的结论和教学意义。