What are the three preparations for a teacher in class?

Teachers' three preparations in class are preparing content, preparing teaching and preparing students. Lesson preparation is all the preparations made by teachers to complete teaching tasks and form teaching ability according to the needs of teaching. Preparing lessons is an important link in the whole teaching process, and preparing lessons well is an important guarantee for good classes. Preparing lessons is not only a teaching design, but also a process of developing, integrating and utilizing teaching resources, internalizing and activating knowledge, learning and paying attention to students, and a process of teachers' re-learning.