Year 4 English: Root words, prefixes, suffixes and word families
Part of the Year 4 English prefixes, suffixes and word families chapter. Chapter overview · whole chapter on one page
Root words, prefixes, suffixes and word families
Many words are built from parts. The root word is the word on its own, such as help. A prefix is added to the start of a root word. A suffix is added to the end.
A word family is a group of words that share one root word, such as help, helpful and helper.
When you meet a new word, take off the prefix and the suffix. What is left is the root word. The parts tell you a lot about the meaning.
| Term | What it means | Example |
|---|---|---|
| root word | a word on its own, which can have parts added | help |
| prefix | letters added to the start of a root word | un- in unhelpful |
| suffix | letters added to the end of a root word | -ful in unhelpful; -ly in helpfully |
| word family | words built from the same root word | help, helpful, helper, unhelpful |
Key ideas
- A root word is a word on its own, such as help.
- A prefix is added to the start of a root word, and it changes the meaning: unhelpful means not helpful.
- A suffix is added to the end of a root word: helpfully has the suffixes -ful and -ly.
- A word family is a group of words built from one root word: help, helpful, helper, unhelpful.
Method. Take off the prefix and the suffix. What is left is the root word.
- Look at the start of the word. A prefix is added before the root word.un-
- Look at the end of the word. A suffix is added after the root word.-ful
- Find the root word. The root word is what is left when the prefix and suffix are taken away.help
- Write the answer. root help; prefix un-; suffix -ful
Check. Put the parts back together to make unhelpful. ✓
Watch out. The root word is a word on its own, or a part that can stand alone.
Method. Think what the sentence means, then choose the word that fits the gap and its spelling.
- Read the sentence with the gap. Think what the sentence means.Please ___ the story before the test on Friday.
- Find the word that fits the meaning. to read something againreread
- Put the word in the gap. Read the sentence again. It makes sense.Please reread the story before the test on Friday.
- Write the answer. reread
Check. Read the whole sentence with reread in it. ✓
Watch out. Re- means again. Read is the root word.
Method. Read the whole word, then fill the box with the affix letters.
- Say the whole word, and look at each part. Read every letter in order.impolite
- Look at the empty box. The box stands for the letters in a row, 2 in all.2 missing letters
- Write the missing letters. Im- is the form of in- before p. Polite starts with p, so in- becomes im-.im
Check. Put im back in the box and read impolite. ✓
Watch out. Im- is the form of in- before p. Polite starts with p, so in- becomes im-.
Watch out
Watch out: a root word is not always the first part of a word. In helpfully, the root word help comes first, then the suffix ful, then ly. Take off the endings one at a time, and check that what is left is a word.
Exam tip
Grown-up tip. Write a long word, such as unhelpful, and ask your child to cross out the prefix and the suffix. Then ask what is left, and what each part means.
Exercise 3A Practice: root words, prefixes, suffixes and families
Method. Match the meaning to the word, then check the prefix or suffix.
- Read the meaning. Think about what the clue describes.not willing to help, or not useful
- Find the word that matches. Think of the one word with this meaning.unhelpful
- Check the affix. Un- means not. Help is the root word, and -ful is the suffix.Affix letters: un
- Write the answer. unhelpful
Check. Read unhelpful and check each letter against the word. ✓
Watch out. Un- means not. Help is the root word, and -ful is the suffix.
Method. Think what the sentence means, then choose the word that fits the gap and its spelling.
- Read the sentence with the gap. Think what the sentence means.The teacher ___ showed us where the books were kept.
- Find the word that fits the meaning. in a way that is useful and kindhelpfully
- Put the word in the gap. Read the sentence again. It makes sense.The teacher helpfully showed us where the books were kept.
- Write the answer. helpfully
Check. Read the whole sentence with helpfully in it. ✓
Watch out. Helpful ends in l, and -ly is added after the -ful, so the word keeps its two l letters before the y.
Method. Read the whole word, then fill the box with the affix letters.
- Say the whole word, and look at each part. Read every letter in order.rewrite
- Look at the empty box. The box stands for the letters in a row, 2 in all.2 missing letters
- Write the missing letters. Re- means again. Write is the root word, and it keeps its silent e.re
Check. Put re back in the box and read rewrite. ✓
Watch out. Re- means again. Write is the root word, and it keeps its silent e.
Method. Compare the wrong spelling with the correct word.
- Look at rered. Compare it with the word reread.rered is not right
- Find the affix. Re- means again. Read is the root word.Affix letters: re
- Write the word correctly. reread
Check. Read reread and check each letter. ✓
Watch out. Re- means again. Read is the root word.
Method. Compare the wrong spelling with the correct word.
- Look at inpolite. Compare it with the word impolite.inpolite is not right
- Find the affix. Im- is the form of in- before p. Polite starts with p, so in- becomes im-.Affix letters: im
- Write the word correctly. impolite
Check. Read impolite and check each letter. ✓
Watch out. Im- is the form of in- before p. Polite starts with p, so in- becomes im-.
Method. Take off the prefix and the suffix. What is left is the root word.
- Look at the start of the word. A prefix is added before the root word.un-
- Look at the end of the word. A suffix is added after the root word.-ful
- Find the root word. The root word is what is left when the prefix and suffix are taken away.help
- Write the answer. root help; prefix un-; suffix -ful
Check. Put the parts back together to make unhelpful. ✓
Watch out. The root word is a word on its own, or a part that can stand alone.
Method. Take off the prefix and the suffix. What is left is the root word.
- Look at the start of the word. A prefix is added before the root word.no prefix
- Look at the end of the word. A suffix is added after the root word.-ful and -ly
- Find the root word. The root word is what is left when the prefix and suffix are taken away.help
- Write the answer. root help; prefix none; suffix -ful and -ly
Check. Put the parts back together to make helpfully. ✓
Watch out. The root word is a word on its own, or a part that can stand alone.
Method. Find the root word of each word.
- Look at helpful and helper. Both are built from the root word help.help + ful; help + er
- Look at hopeful. It is built from hope, not help.hope + ful
- Write the answer. hopeful
Check. Only hopeful is in a different word family. ✓
Watch out. Read the letters of the root word carefully.
Method. Compare the prefix with its meaning.
- Look at unhelpful. Un- means not.un = not
- Look at helpful. Helpful means useful or willing to help, so unhelpful is the opposite.helpful: the opposite is unhelpful
- Write the answer. No. Un- means not, so unhelpful means not helpful. The two words have opposite meanings.
Check. The two words have opposite meanings. ✓
Watch out. A prefix can change a word to its opposite.
Method. Look at the end of helpfully, and compare it with helpful.
- Look at the end of helpfully. The last two letters are ly.-ly
- Compare with helpful. Helpful describes a thing, and helpfully tells how something is done.adjective -> adverb
- Write the answer. -ly. It turns helpful, an adjective, into helpfully, an adverb that tells how something is done.
Check. The suffix -ly makes the adverb. ✓
Watch out. Helpfully ends in -fully, with two l letters.
Method. Think what a root word is, and then build a new word from it.
- Think what a root word is. It is the word on its own, before any prefix or suffix is added.a word on its own
- Give an example. Add un- to help.help + un = unhelpful
- Write the answer. A root word is a word on its own, such as help. Adding un- gives unhelpful.
Check. Help is the root word of unhelpful. ✓
Watch out. The root word is the part that is left when you take off the affixes.
Method. Find the root word, then add a suffix to it.
- Find the root word. Polite is the root word of impolite.polite
- Add a suffix. Add -ly to make politely. Add -ness to make politeness.politely, politeness
- Write the answer. Accept any two correct words, for example: politely and politeness.
Check. Each word is built from the root word polite. ✓
Watch out. Keep the root word spelt the same, with its e.