Hi Linda -- Master Gardeners and Extension do not provide individual consultation. If you brought a samples or photos a full-service garden center might be able to identify the grasses. Otherwise, there are a couple of good websites that describe quackgrass and switchgrass that I think might help in their identification.  In brief, quackgrass can be identified by its clasping auricles, a claw-like appendage at the base of the leaf that wraps around the stem. Also, the underside of the alternate leaves does not have hairs and leaves grows 2 to 12 inches long. Switchgrass leaves also alternate but lack clasping auricles, are hairless except near the base, which is often variously covered in long, silky hairs and leaves grows longer, 7 to 20 inches, than quackgrass.  I hope this helps!