0 Selection window and Delete

Window selection and deletion.

If you want to select the lines created click the bottom right corner of the canvas and then again in the top left.
Doing so will create a "selection window" within which you must include all or part of the lines to select.
You can also click the window first and then top to bottom and from left to right, but beware, in this last case is different because it will select only the objects that are entirely contained within the window.

In later versions of Autocad this selection box is colored in, respectively, green or blue, just to highlight the difference.

Without this, the lines are selected (and become slightly dotted the blue squares appear at the top and center), now press the "Del" key on the keyboard or the delete key   on the modify toolbar.

You can also do the reverse, first activate the command "delete" button on the toolbar, then click the selection box and press "enter" to cancel.

Make some tests of controls that have been described, (line, offset, window selection and delete).