These are past tense verbs/past participles created from base words that end in a voiceless sound, plus the suffix ‘ed’. When we add ‘ed’ it becomes voiceless to match the base word, so it sounds like ‘t’.
When a base word ends with a ‘short’ vowel then one consonant letter, we double the last consonant before adding suffixes starting with vowels. This maintains the “short” vowel sound: a as in capped (not caped), e as in pepped (not peped), i as in pipped (not piped), o as in copped (not coped), u as in supped (not suped).
| Base word ends with 2-3 consonant letters | Double last consonant of CVC base word before adding ed | Double last consonant of longer/more complex base word before adding ed |
| backed bashed batched bossed botched buffed cashed checked chocked chucked chuffed cocked cuffed cussed dashed decked dished dissed ditched docked doffed dossed ducked etched fetched fished fussed gashed gassed gushed hacked hatched hissed hitched hocked huffed hushed itched jacked kicked kissed lacked lashed licked locked lucked mashed massed matched meshed miffed missed mocked moshed mucked mushed nicked notched packed patched pecked picked pitched pocked puffed racked retched rocked rucked rushed sacked shocked shucked socked sucked sussed tacked thatched ticked tossed tucked wished | bopped capped chapped chipped chopped copped cupped dipped hipped hopped kipped lapped lipped lopped mapped mopped napped nipped pepped pipped popped rapped ripped sapped shopped sipped sopped supped tapped tipped topped upped yapped yipped zapped zipped | blipped clapped clipped clopped cropped dripped dropped flapped flipped flopped gripped plopped prepped propped quipped scrapped shipped skipped slapped slipped slopped snapped snipped stepped stopped strapped stripped swapped trapped tripped whipped wrapped |