Page 586 - Practical English Usage 3ed - Michael Swan, Oxford

hoping /,hauprgl later /,lerta(r) I diner /,dama(r)I
hopping /,hDprgl latter /,laata(r) I dinner /,dma(r)I
spelling (8): ch and tch, k and ck 563
7 other exceptions
Consonants are sometimes doubled at the end of final syllables that are pronounced with full vowels (e.g. laa!), even when these do not carry the main stress.
'kidnap -+ 'kidnapped
'handicap -+ 'handicapped
'worship - + 'worshippers ( A m E also 'worshipers) 'combat -+ 'combating or 'combatting
Final -s is sometimes doubled in 1ocus(s)ing and 1ocus(s)ed
8 final c
Final -c changes to ck before -ed, -er, -ing etc. picnic -+ picnickers
panic -+ panicking
mimic -+ mimicked
9 Why double?
The reason for doubling is to show that a vowel is pronounced short. This is because, in the middle of a word, a stressed vowel letter before one consonant is usually pronounced as a long vowel or as a diphthong (double vowel). Compare:
563 spelling (8): ch and tch, k and ck
After one vowel, at the end of a word. we usually write -ck and -tch for the sounds Ik/ and ItSI.
back neck sick lock stuck catch fetch stitch botch hutch
Exceptions:
yak tic public (and many other words ending in -ie) rich which such much attach detach
After a consonant or two vowels, we write -k and -ch. bank work talk march bench
break book week peach coach
564 spelling (9): ie and ei
The sound Ii.:I (as in believe) is often written ie, but not usually ei. However, we write ei after c for this sound. English-speaking children learn a rhyme:
'i before e, except after c'.
believe chief field grief piece shield ceiling deceive receive receipt
Exceptions: seize, Neil, Keith.
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