1： What is pattern ?

Answer ： Drawing that can accurately express the shape, size and technical requirements of an object 。

2： What is projection ？

Answer ： Is a group of rays through the object to a predetermined plane to get the graphic method 。

3： Classification of projection method ？

Answer ： It can be divided into central projection method and parallel projection method ， Parallel projection method is divided into positive projection and oblique projection 。

4： What is sectional view ？

Answer ： A group of parallel rays of light passing through an object on a projection plane

5： What are the three basic views of object projection ？

Answer ： Is the main view. 、 Top view 、 Left view 。

6： Three view What is the projection rule of ？

Answer ： Main 、 Top view Long alignment ； Main 、 Left view Gao Ping Qi ； Bend down 、 Left view Wide equality 。