U u (bus) 【short vowel 短母音】

Some more examples（更多例字）：
• CVC (子音-母音-子音): cub, dub, hub, nub, pub, rub, sub, tub, cud, dud, mud, bud, bug, dug, hug, jug, lug, mug, pug, rug, tug, bum, gum, hum, mum, rum, sum, yum, bun, fun, gun, nun, pun, run, sun, cup, pup, sup, Gus, pus, bus, but, cut, gut, hut, jut, nut, rut

• up, us, thus, plus, bulk, bulb, club, shrub, scrub, snub, stub, stud, spud, thud, buff, cuff, huff, puff, bluff, fluff, gruff, stuff, scuff, chug, drug, shrug, thug, plug, slug, smug, snug, such, much, mulch, munch, bunch, hunch, lunch, punch, crunch, crutch, clutch, gush, lush, mush, rush, hush, shush, slush, flush, plush, blush, brush, crush, buck, duck, luck, muck, puck, suck, tuck, yuck, chuck, pluck, stuck, truck, struck, sunk, bunk, dunk, hunk, junk, punk, chunk, clunk, flunk, trunk, drunk, skunk, dusk, husk, musk, tusk, dull, hull, lull, mull, null, gull, skull, glum, plum, slum, drum, strum, scum, shun, spun, stun, begun, lung, rung, bump, dump, hump, jump, lump, pump, thump, clump, plump, slump, stump, bunt, hunt, blunt, brunt, bust, dust, gust, just, lust, must, rust, crust, trust, thrust, glut, shut, butt, buzz, fuzz, fuss, flux, dusk, duct, Dutch, chuckle, muscle, sudden, suffer, huh, hulk, sulk, gulf, gulp, pulp, pulse, sculpt, cult, culture, bulge, budge, fudge, judge, nudge, grudge, smudge, sludge, plunge, lung, rung, grunt, fund, thunder, under, umbrella, tumble
*mb (silent b): dumb, numb, thumb, crumb

• bubble, buckle, bustle, buffalo, bucket, bunny, buddy, budget, button, butter, customer, custom, culture, culminate, culprit, cunning, chuckle, chubby, clutter, cluster, fluster, flutter, fluctuate, frustrate, funny, funnel, gutter, gullible, hustle, husband, huddle, juggle, justify, justice, luscious, luxury, multiple, muscle, muddle, muffin, mutter, muster, mustard, mushroom, nullify, nuzzle, knuckle, puddle, puppet, public, punish, rubbish, rubber, rudder, rustic, Russia, rupture, rummage, ruffle, rustle, supple, supper, suffer, summer, summit, summon, sullen, sudden, sunny, summary, summarize, sultry, sulfur, suffix, suffocate, subject, supplement, shudder, shuffle, shuttle, smuggle, snuggle, struggle, structure, sculpture, sputter, stubborn, study, tunnel, ugly, upper, utter, ultimate, ulcer, vulgar, vulture, vulnerable, bundle, blunder, clumsy, cumbersome, crumble, fumble, fungus, function, grumpy, grumble, humble, hungry, hundred, junction, jungle, jumble, jumbo, lumber, number, mumble, punctual, punctuate, pumpkin, rumble, rumple, stumble, slumber, Sunday, sundae, truncate, trumpet, thunder, tumble, uncle, under, umpire, adjunct, difficult, impulse, insult, conduct, construct, consult, adult, abrupt, abundance, begun, corrupt, disrupt, discuss, deduct, divulge, expunge, exult, erupt, interrupt, indulge, instruct, obstruct, occult, result, repulse, reluctant, redundant, tumultuous, fundamental, umbrella, reduction, production