Make sure snap mode is on so it has priority. Now, the ends of the sketched line segments always land on the snap points. Remember, if snap is on and the snap increment is much larger than the record increment, the intent of sketching is negated. Object snaps and snap overrides still work while you sketch. Sketched lines don't actually become part of the drawing until you exit the Sketch command or until you specifically instruct AutoCAD to record them.
Toggles pen up and down.
Erases the end section of a sketched line set. It automatically lifts the pen. Move the cursor around and watch as the line segments between the cursor and the newest end of the sketched series disappear and reappear. When you type P or select the pick button, they disappear for good. Pressing E again cancels the erase.