answer:One thing that I didn’t understand is the reason for why the verb is in parentheses in this sentence: In venous insufficiency states, venous blood and refluxes (flows) backwards down the veins into an already congested leg. (From here) I suppose grammar and spelling issues may be too frivolous, but here’s one that stood out: Symptoms of venous reflux disease can include heavy aching, burning, swelling, unsightly cosmetic appearance, skin discoloration, leg fatique and ulcers. After I fulfilled myself in finding that one, I decided it was silly to carry on.