In order to examine whether or not movies can increase students’ listening comprehension, Isnaili, M (2013) and Weyers, J. R. (1999) carried out their experiments and they have come to the similar conclusion that students’ listening skill can be improved through the introduction of movies, especially in a motivated learning environment with “lower level of anxiety” (Isnaili, M. 2013). Besides the listening skill, movies can also enhance students’ visualization skills and reading comprehension. Isnaili, M. (2013) has pointed out that visualization is a very important prerequisite for a good reader. Introducing the movies in the class enables the reader to picture or visualize the events, characters, story and words in the context and it can help students to concentrate on their reading. This enables them to improve their reading comprehension by using their images to have a better understanding of the text (Isnaili, M. 2013).
    From many studies conducted by scholars, it is easy to find out that teachers play an important role in movie appreciation. Yao (2003) thinks that although movie materials are an important text in class, it cannot replace the role of teachers in movie appreciation instruction. Movie text does not exist alone. Its potential can be maximized through explaining, concluding, discussing and evaluating. Hu (2011), Li (2003) and Wei (2003) advocated that teachers should apply constructivism to class teaching----student-centered study. He (1997) also proposed that the educational psychology theory of constructivism emphasizes the focus of students and students are active constructors of learning. Williams, M. and Robert, B. L. (2000) claimed that the role of teachers is to promote the process of constructivism. Teachers should become the helper and facilitator for students to construct the meaning from the instructor of knowledge. In addition, Gu (2005) put forward that when students start to develop the good habit of independent study, they need the supervision and guidance of teachers. Many scholars have proposed that the guidance of teachers is an integral part of movie appreciation instruction, but what teachers should do to maximize the effectiveness of second language acquisition during the instruction deserves our further study.
Many scholars have put forward their opinions about the choice of movie materials since it is of great importance to English learning. Brown, L. J. (2008) has proposed that educationalists are faced with a big challenge of how to balance the relationship between educational and entertaining elements in movie materials. It will be easier for learners to acquire the knowledge from movies if there is a systematical and scientific method to choose the movie materials. Ismaili, M. (2013) claimed that teachers should provide engaging, interesting and up-to-date teaching materials for students and make sure that these materials can be a tool for students. He has also found that students prefer genres such as comedy and action movies. Teachers should avoid the use of over-crowded, violent elements in movie appreciation instruction and the movies should promote comprehension, enhance sensory acuteness and explain the target language（Canning. 1998）. Yao (2003) pointed out that choosing the kinds of movie materials depends on the different capabilities of students and teaching aims. Teachers should apply them effectively in the teaching process. British linguist Lyons (1981) has said that language is not only a biological phenomenon but also a cultural phenomenon. Cultural knowledge is not only subjective knowledge but also the learners’ capability to employ this knowledge. Wei (2008) and Hu (2011) claimed that we should exploit the important cultural information when choosing the movie materials and try to broaden students’ cultural knowledge during the movie appreciation instruction. Moreover, we should also pay attention to the ideological and epochal characters of the content of movies when choosing the movie materials and make sure that they can be understood and accepted by students. Krashen (1982) has pointed out that understanding information is a requirement of acquiring language, and language learners need to input understandable information in order to better understand language. In Balatova’s (1994) experiment, she suggests that video instruction should be encouraged because students who were engaged video and audio conditions got a better understanding of the story than those who listened in audio only conditions. In addition, she said that it is more difficult for students to understand less lively scenes which include long stretches of conversation. Dai and Zhu (2010) have expressed a similar view that the movie materials that we choose should become close to campus life because these materials are easier for students to accept and understand. 看电影对二语习得的影响(2):http://www.youerw.com/yingyu/lunwen_23969.html