Rule Set: Suffixes

Spelling Rule :
Double consonant + (vowel suffix)

short vowel	+	consonant	+	consonant (same as last)	+	vowel suffix
		double consonant
		vowel suffixes: (_ing, _ed, _est, _en, _ish, _ery, _y, _er,)

Rule for short words

single syllable	+	double consonant	+	vowel suffix
clear short vowel sound

Examples: rob – robbing – robbed, slip – slipped – slipping, drop – dropped – dropping, crop – cropped – cropping, clip – clipped – clipping, clop – clopped – clopping, stop – stopped – stopping, grab – grabbed – grabbing

Rule for longer words

first syllable	+	second syllable	+	double consonant	+	vowel suffix
		syllable is stressed and a clear short vowel sound

Examples: compel – compelled – compelling, dispel – dispelled – dispelling, embed – embedded – embedding, repel – repelled – repelling, admit admitted admitting

Don't double

first syllable	+	second syllable	+	vowel suffix
	not a stressed syllable

Examples: listen – listened – listening, render – rendered – rendering

Never double: w, x, v, y, c,

Further info :

short vowel + (double consonant) + (vowel suffix)

When adding a vowel suffix, double the last consonant to keep the short vowel sound.

One syllable words or the stress is on the second syllable with a clear short vowel sound.

(no stress on the second syllable, DON'T DOUBLE)

reference for examples used: https://www.tckpublishing.com/spelling-words-with-double-consonants/