First, the background of the subject In teaching, we found that when students cooperate and communicate, there are always several top students competing to speak, but the vast majority of students have become "machines" that only listen but don't talk. As front-line teachers, we often feel that some children's thinking methods are correct and efficient, while others, including teachers, are at a loss after listening to the children's expressions. These situations show that children's language expression problems have affected their learning quality. "New Curriculum Standard" points out: "Reasoning ability is manifested in obtaining mathematical conjecture through observation, experiment, induction and analogy, and further seeking evidence to prove it; Be able to express the thinking process clearly and methodically, and be reasonable and well-founded; In the process of communicating with others, I can discuss and ask questions logically in mathematical language. " Modern psychology and pedagogy believe that the accuracy of language reflects the thoroughness of thinking, the coherence of language reflects the logic of thinking, and the diversity of language reflects the richness of thinking. This shows that ability and thinking are complementary, and the development of thinking is closely related to the development of language. Therefore, in order to improve students' thinking, reasoning and judgment ability, it is necessary to cultivate students' language expression ability, thus promoting the development of thinking ability. Therefore, the mathematics group of our school has set up a topic, and the sub-topic of how to cultivate students' thinking and expression ability in mathematics teaching is how to cultivate students' expression ability in mathematics teaching. 1 the characteristics of language expression of students in grade and grade four. This year's fourth-grade students are very willing to exchange their ideas with others after class, but when answering questions in class, they often can't express themselves well and explain the topic itself in an orderly way. 2. Investigate and analyze the main reasons that affect students' poor oral expression ability of mathematical language. The "new curriculum standard" emphasizes that learning should proceed from the reality of students and admit that students are constantly developing and full of personality. Students' existing knowledge, ability, emotion, attitude and values will all affect the follow-up study. Therefore, understanding the students' original situation is the basis of our organization research. We can conduct regular or irregular surveys and discussions between teachers and students, observe the current situation of students' speeches in class, find out the reasons why students are unwilling to speak in class, and then study countermeasures. 3. The method of cultivating students' mathematical language expression ability (1) cultivates students' interest and stimulates students' desire to speak. The great role of "interest" in educational practice has been affirmed by many educators at all times and in all countries. German educator Dihuidos described how teachers stimulate and cultivate students' interest: "The art of teaching is not to impart skills, but to inspire, awaken and inspire." Children are in hyperactivity stage, and their attention is often unable to concentrate. Without stable interest, any development of them is impossible. Therefore, to stimulate students' desire to speak, it is necessary to cultivate their interest. (2) Teaching methods and guiding students' speaking skills. (1) The teacher gave a demonstration. ② Train students to learn to listen. (3) Ask students to speak. Mathematical language is different from other languages, because in the dictionary of mathematics, there is only narrative, no description, no metaphor and no exaggeration. Therefore, we require students to speak math language completely, accurately, concisely and methodically. Be concise, crisp and neat, don't drag your feet, let alone add details. (3) Implement the training mode to develop all students' oral ability. To improve the oral language expression ability of all students, we must change the formal group cooperation, flexibly use the training mode of "independent thinking-group discussion-large group communication-practical evaluation", and implement the teaching idea of "language training as the main line and thinking training as the main body" in classroom teaching, so that students at different levels can have more say. In the positive evaluation, students' enthusiasm for speaking is stimulated and their speaking ability is improved. (4) Conduct targeted oral training according to the characteristics of the subject. ① Emphasis should be placed on the essence in concept teaching. (2) Calculation teaching should attach importance to arithmetic. ③ Attention should be paid to expressing ideas in the teaching of practical problems. ④ Attention should be paid to its characteristics in the teaching of geometric figures. (5) Communicate with parents to create a good family atmosphere. Children in lower grades need the active cooperation and guidance of their parents in their studies. Parents and teachers should work together to create a harmonious language expression atmosphere for children and improve their language expression ability. Iii. research objectives 1. Through training and exploration, students can speak mathematical language accurately, concisely and methodically. Promote the development of integrity, orderliness and agility of language and thinking, and develop students' oral expression ability and thinking ability of mathematical language. 2. By cultivating students' mathematical language, the classroom teaching mode is optimized, students' subjective initiative is fully exerted, students' awareness of participation, communication and cooperation is enhanced, students' learning enthusiasm is stimulated, and classroom teaching effect is improved.