Almost all the contrasts occur at the start of the word since /w/ can only occur in syllable-initial position. The spelling of /b/ is <b> throughout. The /w/ sound is <w> or <wh>. Notice how the homograph bow makes pairs with woe and wow and how the partial homograph wear makes pairs with bare and, when capitalised, with beer.
The contrast is between a plosive and a semivowel, close together in the mouth. It is a known problem for Spanish speakers, but it is not a contrast that troubles many other learners.
Pairs involving taboo words are be/wee and bank/wank.
Interesting pairs include:
Billowy, by the way, has the distinction of being one of the few seven-letter words whose letters are in alphabetical order.
The mean density value is 3.8%. The list makes 141 semantic distinctions, a loading of 49%.
abate await abated awaited abates awaits abating awaiting aboard award B we back whack backed whacked backing whacking backings whackings backs whacks backs wax backer whacker backers whackers bacon waken bag wag bagged wagged bagging wagging bags wags bail wail bailed wailed bailing wailing bails wails bails Wales bait wait baited waited baiting waiting baits waits bake wake baked waked bakes wakes baking waking bald walled bale wail baled wailed baling wailing bales wails bales Wales balk walk balked walked balking walking balks walks ball wall balling walling balled walled balls walls bane wane bang whang bangs whangs bangle wangle bangles wangles bank wank banked wanked banking wanking banks wanks bare ware bares wares barer wearer based waist based waste baste waist bastes waists baste waste basted wasted bastes waists basting wasting bate wait bated waited bating waiting bates waits bauble warble baubles warbles bawd ward bawds wards bawd warred bay way bays ways bay weigh bays weighs baying weighing bayed weighed bayed wade be we be wee being weeing beacon weaken beacons weakens bead weed beadle wheedle beadles wheedles beady weedy beak weak beaks weeks beak week beak weeks bear ware bears wares bear wear bears wears bearing wearing bearable wearable beard weird bearer wearer bearers wearers beau whoa beau woe beaux woes beaver weaver beavers weavers bed wed bedded wedded bedding wedding beds weds bee we bee wee bees wees beep weep beeps weeps beer Wear beer weir beers weirs beery weary beerier wearier beeriest weariest beeves weaves bell well bells wells belled welled belling welling belled weld belle well belles wells belt welt belts welts ben wen bens wens bench wench benches wenches bend wend bended wended bending wending bends wends bent went berry wherry berries wherries best west bet wet bets wets betted wetted betting wetting better wetter bey way beys ways bey weigh beys weighs bhang whang bhangs whangs bide wide bides wides bier Wear bier weir biers weirs biff whiff biffs whiffs big Whig big wig bight white bights whites bile while bill will bills wills billed willed billing willing billy willy billies willies billow willow billows willows billowy willowy bind whined bind wind binding winding binds winds bound wound bine whine bines whines bine wine bines wines bird whirred bird word birds words bitch withch bitches witches bitching witching bite white bites whites biting whiting boar war boars wars board ward boards wards boarded warded boarding warding boarder warder boarders warders bode woad bodied wadded body wadi bodies wadis bold wold bond wand bonds wands Bonn wan boo woo booing wooing booed wooed boos woos boom womb booms wombs booze woos bore war bored warred boring warring bores wars bored ward border warder borders warders botch watch botched watched botches watches botching watching botcher watcher botchers watchers bottle wattle bottles wattles bough wow boughs wows bought wart Bourne warn bow whoa bow woe bows woes bow wow bows wows bowed wowed bowing wowing built wilt bull wool bulls wools bully woolly bullies woollies bun one buns ones burr were burr whirr burrs whirrs burke work burked worked burkes works burking working burnt weren't burst worst bursting worsting bursts worsts bury wherry buries wherries buy why buy Y buys Y's buys wise buyer wire buyers wires by Y by why bye Y bye why byes wise forborne forewarn obey away rebound rewound unbind unwind unbinding unwinding unbinds unwinds unbound unwound well-born well-worn
John Higgins, Shaftesbury, January 2010.