how to select multiple waypoints?

Sometimes I want to select say a line of 4 waypoints and duplicate all of them later in the animation. How can I select more than one waypoint at a time? I expected to be able to click and drag and highlight all of them but I can’t do that. Thanks so much for the help. SYNFIG ROCKS!!!

CTRL+left click will add waypoints to selection.
synfig.org/wiki/Mouse_Shortcuts
-G