Suffixes: –ment, –ness, –ful, –less, –ly: what children learn
The good news is that all five suffixes start with a consonant letter, so most of the time they are simply added straight on to the root word with no change at all: care + ful = careful, sad + ness = sadness. The main thing to learn is the exception. When a root word ends in a consonant followed by y, and the root word has more than one syllable, the y changes to i: happy + ness = happiness, penny + less = penniless. Learning that one rule, plus a few special words such as argument, lets children spell hundreds of longer words correctly.
Supports part of Common Core L.3.2.e. This focused game does not cover the entire standard.
Common Core connection: L.3.2.e. This is focused practice for part of the standard.
How to play
Build the word from the tiles. Tap a tile to put it in the next gap, or type the letters. Watch out for the accents! Each game has 8 words and no timer. If a letter is wrong, the right ones stay and you get one more try. You get a point for each word built first time. For a quicker go, choose Quick quiz: 10 multiple-choice questions in 120 seconds (choose Relaxed for more time).
Step by step
- Find the root word. Cover the suffix with your finger and read what is left. In 'helpful' the root is 'help'. Spotting the root first makes spelling longer words feel much less scary.
- Check the first letter of the suffix. –ment, –ness, –ful, –less and –ly all start with a consonant. That means the root word usually stays exactly as it is, even when it ends in a silent e: care + ful = careful, move + ment = movement.
- Look for a consonant + y ending. If the root ends in y with a consonant before it, and the word has two or more syllables (hap-py, mer-ry, beau-ty), change the y to i before adding the suffix: happily, merriment, beautiful.
- Remember the full is only half full. The suffix –ful has only one l. A handy saying is 'the suffix full has lost an l'. Careful, playful, helpful and wonderful all end in a single l.
- Say it, build it, check it. Say the whole word, write the root, add the suffix, then read it back. Does it look right? Checking against a word you already know (hope → hopeful) builds confidence.
Worked examples
Example 1: care + less = ?
Working: –less starts with a consonant, so add it straight on. The e at the end of care stays.
Answer: careless
Example 2: happy + ness = ?
Working: happy ends in a consonant (p) + y and has two syllables, so the y changes to i.
Answer: happiness
Example 3: shy + ness = ?
Working: shy ends in a consonant + y, but it has only one syllable, so the y stays.
Answer: shyness
Example 4: argue + ment = ?
Working: argument is a special word: the e at the end of argue is dropped. It is worth learning on its own.
Answer: argument
Common mistakes and how to fix them
- Writing –full with two ls (carefull). Point out that the suffix is always spelled –ful. Practice a few –ful words together and underline the single l.
- Keeping the y in longer words (happyness, merryment). Clap the syllables of the root word. If there are two or more and a consonant comes before the y, change y to i.
- Dropping the silent e (carless, movment). Explain that the e only drops for suffixes starting with a vowel, such as –ing. Consonant suffixes keep it. argument is the one common exception.
- Missing a doubled letter that belongs to both parts (plainess, enless). Plain + ness keeps both ns because one belongs to plain and one to ness. Build the word from its two parts to see every letter.
Activities to try at home
- Go on a suffix hunt in a favorite book. Every time you find a word ending in –ful, –less, –ness, –ment or –ly, write the root word and the suffix as a sum.
- Make 'word sums' on sticky notes (kind + ness) and stick the answers around the kitchen for your child to find and match.
- Play 'opposites': say a –ful word and ask for the –less word (careful – careless, hopeful – hopeless). Talk about how the meaning changes.
- Use the printable worksheet for a calm five-minute practice, then mark it together using the answer sheet.
Ideas for the classroom
- Sort a pile of word cards into two groups: words where the suffix is added straight on, and words where the y changes to i. Ask students to explain each choice.
- Use mini whiteboards for quick 'word sum' dictation. Read a root and a suffix aloud; students write the new word and hold it up.
- Display a suffix wall with one column per suffix and add new words as students meet them in reading.
- In the game, children build each word from two chunks, such as happi + ness, so they have to choose between happy and happi, or ful and full. Project it for a whole-class warm-up, letting students vote for each chunk before you tap. The Quick quiz asks the same words as multiple-choice questions.
Free printable game and worksheet
The free printable starts with a game sheet, such as a color-by-answer picture, an answer maze or a secret-code joke, followed by a worksheet. Both use the same checked questions as the online game, and the answers are on the last page. Print it, or save it as a PDF from your browser’s print menu.
Open the free printable game and worksheet
Frequently asked questions
How should I choose this game for my learner?
Supports part of Common Core L.3.2.e. This focused game does not cover the entire standard.
Why does happy become happiness but shy becomes shyness?
The y changes to i only when the root word has more than one syllable and a consonant comes before the y. Shy has one syllable, so it keeps its y.
How should I choose this game for my learner?
Supports part of Common Core L.3.2.e. This focused game does not cover the entire standard.
How should I choose this game for my learner?
Supports part of Common Core L.3.2.e. This focused game does not cover the entire standard.