语法是三大基本语言知识之一，它有助于提高交际的准确性和有效性。然而，一些教师可能会发现很难同时保证学生的学习兴趣与学习效率。平衡显性教学和隐性教学，演绎教学和归纳教学一直是教学研究的热点。英语课程标准倡导教育技术和多模式资源的应用。布罗克·布雷迪教授认为其提出的沙漏模式适用于有明显语言特征的教学，如语法和词汇教学。本研究以输入增强理论、认知负荷理论和注意假设为基础，主要描述了多模态PPT辅助下的沙漏模式在初中英语语法教学中的应用，并尝试探索一种语法教学方法。

本研究通过教学实验，检验实验教学模式对学生语法成绩和学习态度的影响。实验是在广东省高峰学校进行的,对象为初三年级的两个平行班，6班（实验组）和4班（对照组），每班40人。在实验之前，作者对两个班的学生进行了语法小测，以确保他们的语法水平相当。同时，对两个班学生的英语语法态度进行了问卷调查。对照组采用传统语法教学方法，辅以单模ppt教学。实验时间为三个月.实验结束后，分别对学生的语法成绩和学习态度进行了语法测试以及问卷调查加访谈。

关于研究结论，首先，多模态PPT辅助下的沙漏模式的应用对学生整体语法成绩有显著影响，在语法使用方面有较大的提高。其次，多模态PPT辅助下的沙漏模式的应用对学生的态度有积极的影响，包括认知维度、情感维度和行为维度三个维度。综上所述，多模态PPT辅助沙漏模型的应用在语法成绩和学习态度上都是有效的。

最后，作者对显性语法教学与隐性语法教学相结合以及语法教学模式的应用提出了一些教学启示和进一步研究的建议。

Grammar is one of the three types of the basic language knowledge and it is helpful to improve the accuracy as well as effectiveness of communication. However, some teachers may find it hard to maintain students’ learning interest as well as assuring learning efficiency. Keeping balance between explicit and implicit teaching, deductive and inductive teaching have been heated topics. The application of educational technology and multi-modal resources are advocated in the English curriculum standard. Professor Brock Brady argues that the Hourglass Model is suitable for teaching with distinct language features, especially grammar and vocabulary teaching. Based on the input enhancement theory, cognitive load theory, and noticing hypothesis, the thesis mainly describes the application of the Hourglass Model assisted by multi-modal PPT in the grammar teaching in junior high school and attempts to explore a grammar teaching method.

A teaching experiment was conducted to check its influence on students’ grammar achievements and learning attitude. The experiment was carried out in Gaofeng school in Guangdong Province. The subjects are two parallel classes , Class 6 (EG) and Class 4 (CG) of Grade Three and the number of each class is 40. Before the experiment, a pre-test of grammar was conducted to ensure the equal grammar achievements of the two classes. At the same time, a questionnaire was conducted on students' attitudes towards English grammar in two classes. The controlled class was taught with a traditional grammar teaching method assisted by mono-model ppt instruction. The duration of the experiment is three months. After the experiment, a grammar test and a questionnaire survey plus interview were conducted on students' grammar achievement and learning attitudes respectively.

As for the findings, firstly, the application of the Hourglass Model assisted by the Multi-modal PPT has significant influence on students’ overall grammar achievements. Greater improvements are shown in the aspects of grammar use. Secondly, the application of the Hourglass Model assisted by the Multi-modal PPT has positive influence on students’ attitude, including cognitive dimension, emotional dimension and behavior dimension. In all, the application of the Hourglass Model assisted by Multi-modal PPT is effective in both grammar achievements and learning attitude.  

Finally, some pedagogical implications on the combination of explicit and implicit grammar teaching and the application of the grammar teaching model as well as some suggestions for further research are provided.