Construction of Flipped Classroom in College English Teaching

China In the era of rapid development of information technology, the field of education continues to promote the process of information, and college English classroom is no exception. The integration of Internet technology and foreign language teaching gives birth to flipped classroom. It is an important trend of college English teaching in the future to combine information technology with classroom teaching and establish an effective evaluation system. Based on the current situation of college English teaching in China, this paper hopes to explore the construction of flipped classroom and improve the teaching


Introduction of Flipped Classroom
The theoretical basis of flipped classroom comes from cognitive load theory and constructivist learning theory. Cognitive load theory was proposed by cognitive psychologist John Sweller in 1988. According to him, cognitive load can be divided into three types: external cognitive load, internal cognitive load, and related cognitive load. These three types of load are superimposed on each other, gradually increasing and expanding students' internal cognitive load, reducing the extra load generated by external interference, and keep students' learning ability within an acceptable range. Flipped classroom essentially reverses the traditional mode, in which teachers preach and students listen and receive, into a completely different one, in which students solve a series of problems encountered in pre-class learning according to their cognitive load ability through the teacher's explanation and classroom discussion, so that the students can truly acquire the knowledge and reduce the cognitive load.
Constructivist learning theory originated in the 1980s and was proposed by Jean Piaget, a Swiss psychologist. This theory holds that learning is an active construction of knowledge by individual learners, with a process of discovering and processing new information, and gradually generating self-cognition on the basis JIN Zhao-hui, master of Arts, lecturer, College of Foreign Languages, University of Shanghai for Science and Technology, Shanghai, China. of the accumulation of original knowledge. Constructivism advocates the student-centered concept, attaches importance to the individual differential development of students, encourages them to solve problems according to their own experience, and emphasizes the interaction between students and teachers. Under the flipped classroom teaching mode, students can have a good understanding of knowledge through pre-class video learning. Then, they can communicate and interact with teachers or other students in classroom to solve the problems that still exist and build their own knowledge system.
Flipped classroom, also known as inverted classroom, transfers knowledge imparting to the pre-class practice, and transmits the related information to the students through micro class or other online teaching methods. Students complete the knowledge independently before class, discussing and communicating with other students and teachers through the network platform. In classroom, teachers do not explain and indoctrinate knowledge or the language points that have been put on the Internet, but guide and answer questions according to the results of students' learning before class. In the classroom practice, teachers usually divide students into several groups and arrange for exploratory activities, so that students can achieve common improvement in the process of collaborative exploration. Teachers will evaluate the results of each group. At the end of classroom teaching, teachers need to guide students to conduct a systematic review and summary of the knowledge involved in this course, and to develop a thorough analysis of some practical problems arising in learning. Under such teaching mode, classroom efficiency is improved, with the interaction between teachers and students strengthened.

Conducive to the Cultivation of Students' Autonomous Learning Ability
Traditional teaching mode restricts the development of students' autonomous ability to a large extent, and students passively accept the knowledge transferred from teachers. As a result, students become dependent on teachers and cannot solve the problems they encounter independently, which will have a negative impact on the internalization of knowledge. Flipped classroom, on the other hand, adjusts the order of knowledge transfer and knowledge internalization. First, students learn independently online and then solve problems that occur in this autonomous learning process through the guidance of teachers in classroom, which is more conducive to the internalization of knowledge. This new teaching mode can effectively mobilize students' learning enthusiasm. In the meanwhile, it also provides students with more free space. Students will gradually eliminate their dependence on teachers and form the consciousness of independent exploration and learning. In class, students will have more space for self-expression and can achieve sound language output on the basis of completing language input, which can gradually build up students' learning confidence.

Contributing to the Improvement of Classroom Efficiency
In traditional classes, teachers impart knowledge with students learning passively. There is not enough time for teachers to explain all the background information and language points, and there is little communication and interaction between teachers and students. Due to the limited time, it is difficult for students to express their opinions or ask questions, therefore high classroom efficiency is hard to achieve. In flipped classroom, teachers will explain and answer questions in a targeted way, so that students will gain a lot in the classroom. Classroom time is largely saved so that students will discuss and explore the concerning topics with group members in a deeper level, which facilitates the critical thinking development as well.

Beneficial to Improve the Evaluation Method
The traditional teaching evaluation method is summative evaluation, that is, the students' score in a final examination is taken as the evaluation result of the course, and the evaluation method is single and one-sided. The flipped classroom mode enables teachers to control and monitor the whole learning process of students from pre-class preparation, question-answering in classroom to after-class summary. Teachers can design various formative evaluations based on a series of learning processes. This kind of evaluation method is more detailed and comprehensive, with a presentation of the whole picture of students' learning process. Under such evaluation system, students can better understand their own level, which is constructive to their planning of further learning.

Pre-class Session
The preparation of materials before class should be adequate and proper as to the degree of difficulty. The most common carrier of flipped classroom in college English teaching is micro-class video. In order to ensure the teaching effect, teachers should sort out the teaching content, put forward key and difficult points, and provide the relevant videos. The content of the video should include vocabulary, grammar, cultural background, etc., which should be both informative and interesting. The duration should be controlled within 10-15 minutes. Students should watch the videos before class, through which they can have a global picture of what they are going to learn in the unit, where they should pay special attention to, and what difficult points they are expected to work hard. More often than not, they will have an expansion of the text with the background information. If the materials are intriguing, students are more likely to dig more about the content in the text for themselves online.

Classroom Activities
The core of flipped classroom is the communication and interaction between teachers and students. In the classroom teaching, teachers should adopt the method of group teaching, integrate the actual situation of all students to make a scientific group design, and then determine the time and rules for group discussion. Teachers can use multiple teaching methods to build an English-learning environment such as grouped discussions, debates, reports, case analysis, and so on, which can let the students solve issues by using the knowledge they have learned. During the process, teachers will answer the questions raised by students specifically, monitor and control the process of the classroom activities, have a more far-reaching discussion on those existing problems, and incorporate the performance in discussion and results into the formative evaluation.
In the whole process mentioned above, teachers should always guide students instead of directly interfering with their thinking and learning. Meanwhile, they should pay attention to the reasonable allocation of time to ensure the teaching effect.
At the end of the class, there should be the final feedback and summary part as well. In the conclusion session, teachers should try their best to go to the point with concise and powerful language. They are supposed to summarize the important points and problems that should be paid special attention to, give comments on the students' performance, and assign after-class tasks to consolidate the results of teaching and learning.

Dynamic Evaluation
In the flipped classroom evaluation system, improvements need to be made. Teachers can introduce more pluralistic evaluation methods and items on the basis of the past sole final exam-centered index. The evaluation CONSTRUCTION OF FLIPPED CLASSROOM IN COLLEGE ENGLISH TEACHING 234 system should be a dynamic one including students' pre-class learning results, their performance in the classroom activities and the completion of their assignments.
Teachers should especially pay attention to the questions that students ask in the classroom, which may indicate difficult points in the pre-class learning. In the process of Q and A, teachers should carefully evaluate students' answers and correct them in time, which facilitates students to develop self-learning ability and their personalities. In the open discussion part, teachers should grade each student according to his contribution and language proficiency. Assessment of assignments should be targeted at the key points and difficulties in the knowledge points. Teachers should find out students' problems and solve them timely.

Possible Problems
Amidst the popularity of flipped classroom mode in recent years, there are still possible problems. First of all, influenced by traditional teaching mode, it is hard to change their roles either for teachers or students. Students are still expecting teachers to "feed" them with language points instead of actively learning or exploring before class. In the classroom, they are not likely to express themselves, but would rather listen to others or wait for the answers.
Secondly, not all the teachers can be good organizers of classroom activities. Organizing is a job that involves talent, personality, personal horizon, and many other factors. If the activity is organized inefficiently, it is no less than a disaster in the classroom.

Conclusion
To sum up, in the era of information networks, introducing the flipped classroom into college English learning contributes to the cultivation of students' autonomous learning abilities and the implementation of students' dominant role in teaching and learning process. Meanwhile, the new classroom mode proposes higher demand both for teachers and students. Teachers should recognize their own limitations, be fully aware of the roles that students and teachers play, and strengthen their command of instructional theories and information technology. Students should actively take part in the pre-class learning and classroom activities. Only in this way can they keep pace with the times and explore new methods of college English teaching and learning continuously.