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You have used prefixes before. Mia and Leo are making the lesson's cake. Mia misread 'one spoon of sugar' as 'two spoons'.
What does misread tell you about Mia's reading?
به انگلیسی
Verb Prefixes and Meaning
Use verb prefixes (dis-, de-, mis-, over-, re-) to change verb meaning. Understand how each prefix changes the action expressed by the root verb.
What a learner can do afterwards
- Add verb prefixes to change meaning, using established words such as disagree, disappear, defrost, misunderstand, misbehave, overcook, overreact, redo and reconsider.
- Select a prefix for a stated meaning: dis- for not or opposite, mis- for incorrectly, de- or un- for removal or reversal, re- for again, and over- for excess.
- Use sentence context to distinguish a prefixed verb from a prefixed noun or adjective, and explain how the prefix changes the verb's meaning.
1 · Read
A prefix goes before a base word and changes its meaning. A prefix added to a verb changes the action described: redo means do again. Prefixes also occur in other word types. Unhappy is an adjective describing a feeling. In 'I wore my overcoat', overcoat is a noun naming clothing. Use the sentence to check how a word is used.
Dis- can mean not or opposite: disagree means not agree; disappear means go out of sight. Mis- means incorrectly, as in misread. De- can mean remove or reverse: defrost means remove frost or thaw frozen food. Re- can mean again, as in redo. Over- can mean too much: overcook means cook too long. These are meaning clues. Use the sentence too. Use established words; do not attach any prefix to any verb.
Try it together
Mia misread 'one spoon of sugar' as 'two spoons'. Leo baked the cake too long and overcooked it. They will redo the cake, which means make it again.
Un- can reverse an action. Untie undoes tying, unpack means take out what was packed, and unlock undoes locking. Unlocking a door does not mean you have opened it. Some words only begin with familiar prefix letters. Uncle does not contain un- meaning reverse, and disaster does not contain dis- meaning not.
A suffix goes after a base: helpful is help + -ful, and sadness is sad + -ness. Replay has re- before the verb play. Context also helps with meaning. 'I mistook Ali for Sam' means I thought Ali was Sam. Mis- signals that mistake; it does not mean I physically took a person.
Good to know
Look for a known base word. Check the word's job in the sentence, then use the prefix and context together. A dictionary can help when the meaning is unclear.
Verb prefixes like dis-, de-, mis-, over-, re-, and un- change what the action itself means.
Original lesson, practice and learning-card text written for this dataset. Khan Academy word-study records informed factual checks and question design.
Two independently written readings about prefixes and word types prepared for this dataset. Khan Academy word-study records informed factual checks.
More to read
Use the prefix and the sentence
A sign says, 'Please reload the basket.' Re- tells us to load it again. The sentence tells us what is being loaded.
Another sign says, 'Do not overload the basket.' Over- warns about putting too much into it.
Misread means read incorrectly. Disagree means not agree. Defrost means remove frost or thaw something frozen. Unpack means take out what was packed.
These examples offer useful clues. They do not mean every prefix can be attached to every verb. Use a word you know, or check a dictionary.
Some whole words need extra care. If someone mistook a friend for their cousin, they confused the two people. They did not pick up or carry the friend. Read the surrounding words as well as the prefix.
Check the word part and its job
Compare replay and playful. Replay has re- before play. Playful has -ful after play. A part added before a base is a prefix; a part added after it is a suffix.
Read: 'We replay the tune.' Replay is a verb describing an action. In 'I wore my overcoat', overcoat is a noun naming clothing. Both words have prefixes, but only replay is a verb in these sentences.
Unhappy is an adjective describing a feeling.
A familiar beginning is not always a prefix. Uncle does not contain un- meaning reverse. Disaster does not contain dis- meaning not. Check the base and the whole word's meaning as well as its first letters.
2 · Watch
به انگلیسی3 · Play
به انگلیسی
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