The tables below summarize the basic spelling rules for endings with verbs, nouns, adjectives, and adverbs.
| Rule | Word | -s | -ed | -er | -est | -ing |
| For most words, simply add –s, -ed, -er, -est, or –ing without making any other changes. | Clean | Cleans | Cleaned | Cleaner | Cleanest | Cleaning |
| Cool | Cools | Cooled | Cooler | Coolest | Cooling |
However, spelling changes occur in the following situations:
| Rule | Word | -s | -ed | -er | -est | -ing |
| For words ending in a consonant +y, change the y to i before adding –s, -ed, -er, or –est. Do NOT change or drop the y before adding -ing. | Carry | Carries | Carried | Carrier | Carrying | |
| Happy | Happier | Happiest | ||||
| Lonely | Lonelier | Loneliest | ||||
| Study | Studies | Studied | Studying | |||
| Worry | Worries | Worried | Worrier | Worrying | ||
| For most words ending in e, drop the e before adding –ed, -er, -est, or –ing (there are exceptions*) | Dance | Danced | Dancer | Dancing | ||
| Late | Later | Latest | ||||
| Nice | Nicer | Nicest | ||||
| Save | Saved | Saver | Saving | |||
| Write | Writer | Writing | ||||
| For many words ending in one vowel and one consonant, double the final consonant before adding –ed, -er, -est, or –ing. This rule is applied to one syllable words and words with stress on the final syllable. | Begin | Beginner | Beginning | |||
| Hot | Hotter | Hottest | ||||
| Mad | Madder | Maddest | ||||
| Plan | Planned | Planner | Planning | |||
| Occur | Occurred | Occurring | ||||
| Refer | Referred | Referring | ||||
| Run | Runner | Running | ||||
| Shop | Shopped | Shopper | Shopping | |||
| Win | Winner | Winning | ||||
| In the words ending in one vowel and one consonant, do not double the final consonant if the last syllable is not stressed. There are exceptions** | Enter | Entered | Entering | |||
| Happen | Happened | Happening | ||||
| Open | Opened | Opener | Opening | |||
| Travel | Traveled | Traveler | Traveling | |||
| Visit | Visited | Visiting | ||||
| For most words ending in -f or -lf change the f to v and add –es. There are exceptions *** | Half | Halves | Halved | Halving | ||
| Loaf | Loaves | |||||
| Shelf | Shelves | Shelved | Shelving | |||
| For words ending in ch, sh, s, x, z, and sometimes o, add –es. There are some exceptions **** | Church | Churches | ||||
| Wash | Washes | |||||
| Class | Classes | |||||
| Fix | Fixes | |||||
| Quiz | Quizzes | |||||
| Tomato | Tomatoes | |||||
| Zero | Zeroes |
*Exceptions
agree – agreeing
canoe – canoeing
**Exceptions
bus – busses – bused – busing
fix – fixed – fixer – fixing
play – played – player – playing
sew – sewed – sewer – sewing
***Exceptions
belief – beliefs
chief – chiefs
proof – proofs
roof – roofs
safe – safes
****Exceptions
dynamo – dynamos
ghetto – ghettos
monarch – monarchs
piano – pianos
portfolio – portfolios
radio – radios
studio – studios
Irregular Noun Plurals
| Singular | Plural |
| Person | People |
| Child | Children |
| Man | Men |
| Woman | Women |
| Foot | Feet |
| Tooth | Teeth |
| Deer | Deer |
| Fish | Fish |
| Goose | Geese |
| Ox | Oxen |
| Series | Series |
| Species | Species |