Changing Object's Shape
Erase a Part of an Object
The Eraser tool can remove a part of an object. This tool also works with groups and compound groups.
To activate the Eraser tool, click on the Eraser icon in the Tools panel.
In order to erase a portion of an object, select this object. Then drag the tool over the object's part you want to remove.
If the original object is created by a closed path, the program will keep it closed. After applying the Eraser tool to the path, the latter will either change its shape or split into two closed paths.
In order to move the Eraser tool along a straight line, use the Opt key. Press it before dragging the tool. In order to snap the line to 45, 90 degrees and so on, hold down the Opt and Shift keys.
To change the tool width, use these keys: [ to decrease, and ] to increase.