forb means relatively broad and pinnately-veined leaves
grass-like means relatively narrow and parallel-veined leaves

The list of plants:

Bacopa caroliniana -- southeastern U.S. -- lemon bacopa - forb - emersed
Bidens laevis -- entire U.S., except central -- bur-marigold - forb
Brasenia schreberi-- most of U.S. and Canada -- water shield - forb - floating-leaved
Cephalanthus occidentalis-- eastern half, U.S. and Canada -- buttonbush - tree
Cladium jamaicense -- southeastern U.S. -- saw-grass - grass-like
Crinum americanum -- southeastern U.S. -- swamp lily - forb
Cyperus odoratus -- entire U.S., except northwest -- rusty flat sedge - grass-like
Eleocharis interstincta -- this spikerush is in southeastern U.S. -- giant spikerush - grass-like
Equisetum hyemale -- entire U.S. and Canada -- horsetail - forb
Eragrostis elliottii -- this love grass is in southeastern U.S. -- Elliott's love grass - grass-like
Fimbristylous cymosa -- this fimbry grass is in Florida only -- hurricane-grass - grass-like
Hibiscus coccineus -- southeastern U.S. -- scarlet rosemallow - forb
Iris virginica -- this blue flag is in eastern half of U.S. and Canada -- blue flag - forb
Juncus effusus -- this rush is in entire U.S. and Canada -- soft rush - grass-like
Lachnanthes caroliniana -- southeastern U.S. and eastern seaboard -- redroot - forb
Limnobium spongia -- southeastern U.S. to mid-west and NY -- frog's-bit - forb - floating-leaved
Lobelia cardinalis -- most of U.S. and eastern Canada -- cardinal flower - forb
Ludwigia leptocarpa -- southeastern U.S. to PA -- hairy primrose-willow - shrub
Nelumbo lutea -- eastern 2/3rds U.S. and CA -- American lotus - forb - floating-leaved
Nuphar advena -- entire U.S. to northern Canada -- spatterdock - forb - floating-leaved
Nymphaea odorata -- eastern half U.S. and Canada -- fragrant water lily - forb - floating-leaved
Nymphoides aquatica -- eastern half U.S. and Canada, and far west -- banana lily - forb - floating-leaved
Panicum hemitomon -- this panic grass is in southeastern U.S. -- maidencane - grass-like - emersed
Paspalidium geminatum -- southeastern U.S. -- Egyptian paspalidium - grass-like - emersed
Peltandra virginica -- eastern half U.S. and Canada, and far west -- green arrow arum - forb - emersed
Polygonum densiflorum -- this knotweed is in southeastern U.S. to PA -- giant smartweed - forb - emersed
Pontederia cordata -- eastern half of U.S. and Canada -- pickerelweed - forb - emersed
Potamogeton nodosus -- this pondweed is in entire U.S., most of Canada -- longleaf pondweed - forb - floating-leaved
Rhynchospora colorata -- this beakrush is in southeastern U.S. -- star-rush - grass-like
Sagittaria lancifolia -- this arrowhead is in southeastern U.S. -- bulltongue arrowhead - forb - emersed
Sarracenia minor -- this pitcher plant is in extreme southeastern U.S. -- hooded pitcher plant - forb
Saururus cernuus -- eastern half of U.S. and Canada -- lizard's-tail - forb - emersed
Scirpus validus -- this bulrush is in entire U.S. and Canada -- soft-stem bulrush - grass-like
Spirodela polyrhiza -- entire U.S. and most of Canada -- giant duckweed - forb - floating-leaved
Thalia geniculata -- FL, GA, LA -- alligator flag - forb
Utricularia radiata -- this bladderwort is found from TX to ME -- little floating bladderwort - forb - submersed-floating
Vallisneria americana -- most of U.S. and southern half of Canada -- tape grass - forb - submersed
Xyris ambigua -- this yellow-eyed-grass is in southeastern U.S. -- morning yellow-eyed-grass - forb
Zephyranthes atamasco -- southeastern U.S. -- Atamasco-lily - forb
Zizania aquatica -- this wild rice is in eastern half of U.S. and Canada -- wild rice - grass-like