Appendix 5 – Spelling Rules

5.1 Words + -s and -es (birds/watches etc.)
noun + s (plural) (→ Unit 65)
birdbirds
mistakemistakes
hotelhotels
verb + s (he/she/it + s) (→ Unit 5)
thinkthinks
livelives
rememberremembers
+ es after -s / -sh / -ch / -x:
busbuses
dishdishes
watchwatches
boxboxes
addressaddresses
finishfinishes
passpasses
washwashes
teachteaches
sandwichsandwiches
tomatotomatoes
potatopotatoes
gogoes
-f / -fe → -ves:
shelfshelves
knifeknives
roofroofs
5.2 Words ending in -y (baby → babies / study → studied etc.)
-y → -ies:

study → studies (not 'studys')

studystudies
storystories
citycities
familyfamilies (not 'familys')
babybabies
flyflies
trytries
marrymarries
-y → -ied (→ Unit 11):
studystudied (not 'studyed')
trytried
marrymarried
copycopied
-y → -ier/-iest (→ Units 86 and 89):
easyeasier/easiest (not 'easyer/easiest')
happyhappier/happiest
heavyheavier/heaviest
luckyluckier/luckiest
funnyfunnier/funniest
-y → -ily (→ Unit 85):
easyeasily (not 'easyly')
happyhappily
luckyluckily
heavyheavily

y does not change to i if the ending is -ay/-ey/-oy/-uy:

holidayholidays (not 'holidaies')
enjoyenjoys/enjoyed
staystays/stayed
buybuys
keykeys

but say → said pay → paid (irregular verbs)

5.3 -ing
Verbs that end in -e (make/write/drive etc.) → -ing:
makemaking
writewriting
comecoming
dancedancing
Verbs that end in -ie → -ying:
lielying
diedying
tietying
5.4 stop → stopped, big → bigger etc.
Vowels and consonants:

Vowel letters: a e i o u

Consonant letters: b c d f g h j k l m n p q r s t v w x y z

Sometimes a word ends in a vowel + a consonant. For example: stop, big, get, etc.

Before -ing/-ed/-er/-est, the consonant at the end is doubled (p→pp / g→gg / t→tt etc.)

V+C
stop S T O P p → pp stopping
stopped
run R U N n → nn running
runner
get G E T t → tt getting
swim S W I M m → mm swimming
big B I G g → gg bigger
biggest
hot H O T t → tt hotter
hottest
thin T H I N n → nn thinner
thinnest

This does not happen:

(1) if the word ends in two consonant letters (C + C):

help HE L P → helping → helped
work WO R K → working → worked
fast FA S T → faster → fastest

(2) if the word ends in two vowel letters + a consonant letter (V + V + C):

need N E E D → needing → needed
wait W A I T → waiting → waited
cheap CH E A P → cheaper → cheapest

(3) in longer words (two syllables or more) if the last part of the word is not stressed:

happen HAP-pen → happening/happened (not 'happenned')
visit VIS-it → visiting/visited
remember re-MEM-ber → remembering/remembered

but prefer pre-FER (stress at the end) → preferring/preferred

begin be-GIN (stress at the end) → beginning

(4) if the word ends in -y or -w. (At the end of words, y and w are not consonants.)

enjoy → enjoying/enjoyed
snow/showing/snowed