The same as you do for other elements, by holding the SHIFT key to add or subtract from your selection set.
But because you are talking about individual edges of a morph, you must make sure that the selection tool is in sub-element mode.
Or use CTRL+SHIFT to temporarily enter sub-element selection mode.
The CTRL key toggles this mode on while you hold it.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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