(1) knowledge of plane graphics

① Characteristics, connections and differences of straight lines, rays and line segments.

② Characteristics, classification and measurement methods of angles.

③ Vertical and parallel.

(4) Characteristics and classification of triangles (by edge and angle).

⑤ quadrilateral. The characteristics of each kind of graphics, the relationship between special and general.

⑥ Circle and sector. The characteristics of circle, diameter and radius, and the relationship between sector and circle.

⑦ Axisymmetric graphics. (Can draw the symmetry axis of the learned axisymmetric figure)

Requirements: ① Grasp the characteristics, establish contact, and let students feel the connection from point to line, from line to surface, and from surface to body.

② Reasonable judgments and choices can be made according to the graphic features.

(2) the perimeter and area of the plane figure

① Understand the concepts of perimeter and area.

(2) Master the calculation formula and derivation process of the perimeter and area of each figure.

③ Formulas can be used flexibly to solve problems.

① Features of cuboids, cubes, cylinders and cones.

(2) The relationship between length and cube.

(3) the surface area and volume of three-dimensional graphics

② Find the surface area and volume of cuboid, cube and cylinder; The volume of a cone.

(3) Establish the connection of volume calculation of these four kinds of three-dimensional graphics.

④ Strengthen the contrast training of the difference between volume and surface area and the difference between volume and volume.

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