1, monomials and polynomials: knowledge points for learning their definitions and related applications;

2. Coefficient and index: learn relevant knowledge points about the difference and connection between coefficient and index;

3. Merge similar items: learn their definitions and related knowledge points;

4. Radical and arithmetic square root: learn its definition and related application knowledge points;

5. Statistics and the formula of circle: statistics includes the knowledge points of population, individual, sample, sample size, mode and median, and circle includes the knowledge points of the definition of circle and its related formulas;

6. Algebraic expressions and fractions, algebraic expressions and rational expressions: Learn the definitions of four expressions and their related knowledge points.