2. Click the "A" button in the upper left corner.
3. Find the "Options" button in the lower right corner in the drop-down list, and then click it.
4. Select "User System Configuration" in the pop-up dialog box, and click the "Initial Settings" button in the lower left corner.
It can be seen that the present environment is "civil engineering". Select the environment that needs to be changed.
6. Then click the "Finish" button in the lower right corner. This changes the working environment of CAD.