1. Tangram consists of the following seven plates. The complete pattern is a square: five isosceles right triangles (two small triangles, one middle triangle and two large triangles), a square and a parallelogram.

2. Square: Put the two largest triangle blocks together to form a big isosceles triangle. The trapezoidal block and the two smallest triangular blocks are arranged in a straight line next to the longest side of the large isosceles triangle, and the remaining medium-sized triangular blocks are put together in the lower left corner.

3. Rectangular, the largest two triangles are placed in the lower right corner, the longest side contact point is placed in the lower left corner, the middle right-angled triangle block is placed, the two right-angled sides next to it are the longest and largest triangles, and the remaining small triangles, squares, small triangles and trapezoidal blocks are spliced from left to right.

4. Triangle: Assemble the two largest triangles into a big triangle, with a right-angled side on the left, a trapezoid block of a middle triangle from top to bottom, and a small triangle block and a square block on the right. Jigsaw puzzle-skilled shape matching.