# Spelling Rules for Adding Suffixes

- Link: https://thecuriosi.com/lessons/suffix-spelling-rules/
- Published: 2026-10-31T14:57:07+05:30
- Author: MAHENDRA MANCHIKALAPATI

1. [Courses](https://thecuriosi.com/courses/)
 2. [Vocabulary Builder: Roots, Prefixes and Suffixes](https://thecuriosi.com/courses/greek-and-latin-roots-vocabulary/)
 3.  Lesson 5 of 10

You know that adding suffixes creates new words. But sometimes the base word changes
its spelling when a suffix is added. _Hope_ becomes _hoping_, _happy_ becomes _happiness_,
and _run_ becomes _running_. These changes follow patterns. In this lesson you will
learn four spelling rules that cover most words.

### First: vowel suffixes and consonant suffixes

First, notice whether the suffix starts with a **vowel** or a **consonant**. This
matters for every rule.

 * **Vowel suffixes**: -ing, -ed, -er, -est, -able, -ous, -ion
 * **Consonant suffixes**: -ful, -less, -ness, -ment, -ly

## Rule 1: drop the silent e

When a word ends in a **silent e**, drop the e before adding a **vowel** suffix.
Keep the e before a **consonant** suffix.

  |  Base |  + vowel suffix |  + consonant suffix |  
   |  hope |  hoping, hoped |  hopeful |  
 |  care |  caring |  careful, careless |  
 |  use |  usable |  useful |  
 |  move |  movable |  movement |

### Common exceptions

Words ending in **-ce** or **-ge** keep the e before _-able_ or _-ous_ to keep the
soft sound: _noticeable_, _courageous_, _manageable_. And _argue_ + _-ment_ drops
the e to make _argument_.

## Rule 2: change y to i

When a word ends in a **consonant + y**, change the y to **i** before adding most
suffixes.

 * happy → happiness, happily, happier
 * beauty → beautiful
 * carry → carried

But **keep the y** before _-ing_, so you do not get two i’s in a row: _carrying_,
_studying_, _trying_.

### When the y stays

If the word ends in a **vowel + y**, keep the y: _play_ → _played_, _enjoy_ → _enjoyment_,
_employ_ → _employer_.

## Rule 3: double the final consonant

Double the last consonant before a vowel suffix when the word:

 1. has **one syllable** (or the **stress** is on the last syllable),
 2. ends in **one vowel followed by one consonant**.

  |  Base |  Suffix |  New word |  
   |  run |  -ing |  running |  
 |  stop |  -ed |  stopped |  
 |  big |  -est |  biggest |  
 |  begin |  -ing |  beginning (stress on _gin_) |  
 |  forget |  -able |  forgettable |

### Do not double when…

 * The word ends in **two consonants**: _jump_ → _jumping_.
 * The word has **two vowels** before the consonant: _rain_ → _raining_.
 * The suffix starts with a **consonant**: _ship_ → _shipment_.
 * The stress is **not** on the last syllable: _visit_ → _visited_, _open_ → _opened_.

### Example

Why is it _preferred_ but _preference_? In _preferred_, the stress stays on the 
last syllable of _prefer_, so we double the r. In _preference_, the stress moves
to the first syllable, so we do not. Saying the word aloud helps you hear the difference.

## Rule 4: just add it

For most other words, simply add the suffix with no changes: _help_ → _helpful_,
_quick_ → _quickly_, _kind_ → _kindness_.

### A tricky -ly pair

Notice _careful_ → _carefully_: the base already ends in _l_, so adding _-ly_ gives
two l’s. The same happens with _real_ → _really_ and _final_ → _finally_.

### When in doubt

English spelling has exceptions, so if a word looks strange after you add a suffix,
check a dictionary or spell checker. Over time, the rules become automatic.

## Key takeaways

 * Drop a silent e before a vowel suffix, but keep it before a consonant suffix.
 * Change consonant + y to i, except before -ing.
 * Double the final consonant after a single short vowel in a stressed final syllable.
 * Otherwise, just add the suffix, and say words aloud to check stress.

## Practice

Add the suffix and spell the new word: **1.** make + ing, **2.** cry + ed, **3.**
swim + er, **4.** enjoy + able, **5.** hope + less, **6.** admit + ed.

Answers: 1 making. 2 cried. 3 swimmer. 4 enjoyable. 5 hopeless. 6 admitted (stress
on _mit_).

 [Log in](https://thecuriosi.com/wp-login.php?redirect_to=https%3A%2F%2Fthecuriosi.com%2Flessons%2Fsuffix-spelling-rules%2F)
to mark lessons complete and track your progress.

 [ Previous lesson Suffixes That Change a Word’s Job ](https://thecuriosi.com/lessons/suffixes-parts-of-speech/)
[ Next lesson Greek Roots ](https://thecuriosi.com/lessons/greek-roots/)

 [Back to course overview](https://thecuriosi.com/courses/greek-and-latin-roots-vocabulary/)

Share this