2. Equations and functions: one-dimensional linear equation, one-dimensional quadratic equation, two-dimensional linear equation, one-dimensional quadratic function and inverse proportional function. Understand which unknown is y and which is X.

3. Geometry: straight line, ray, line segment, triangle, quadrilateral, circle and their positional relationship, triangle pythagorean theorem, similar triangles proportional relationship.

4. Factorization of algebraic expressions (this is very important, and I found that many students can't do this when teaching).

These seem like a lot, but they are not difficult to learn, just like 1+ 1=2 we learn in primary schools now. I wonder if my answer satisfies you?

Come on! You can ask me again if you don't meet anywhere.