The /g/ sound is spelled with <g>, <gg> or <gu> in guide. The /ʧ/ sound is spelled <ch> or <tch>.
The contrast is between a voiced velar stop and a voiceless palatal affricate. It does not cause any problems.
Interesting pairs include:
The mean density value is 2.5%. The list makes 68 semantic distinctions, a loading of 61%.
augured orchard bag batch berg birch big bitch bog botch bogging botching brogue broach dagger dacha daggers dachas dig ditch digging ditching Doug Dutch dug Dutch egg etch egging etching gad Chad gain chain gained chained gaining chaining gains chains gamp champ gamps champs gap chap gaps chaps garter charter garters charters gat chat gaud chawed gauze chaws gawk chalk gawks chalks gawky chalky gawkier chalkier gawkiest chalkiest gear cheer geared cheered gearing cheering gears cheers gild chilled gill chill gills chills gillie Chile gillie chilli gillies chillies girl churl girls churls girlish churlish girlishly churlishly goes chose goo chew gore chaw gores chaws gored chawed gore chore gores chores Gorky chalky guard Chard guess chess guessed chest guest chest guests chests guide chide guided chided guides chides guiding chiding guild chilled gum chum gummed chummed gumming chumming gums chums gummy chummy gummier chummier gummiest chummiest hag hatch hug hutch keg ketch lag latch lagging latching league leach leaguing leaching league leech mag match mug much pig pitch pigging pitching piggies pitches quagga kwacha rag ratch rig rich rigger richer rogue roach scrag scratch scragging scratching scraggy scratchy scraggier scratchier scraggiest scratchiest snag snatch snagging snatching stagger stature swig switch swigging switching tug touch tugging touching twig twitch twigging twitching vulgar vulture Whig which Whig witch wig which wig witch wigging witching
Credit: John Higgins