Name _______________________________________

Lesson 29 Paired prefixes


mis + stated = misstated ad + tain = attain
un + stated = unstated com + tain = contain
dis + sect = dissect ex + fort = effort
in + sect = insect com + fort = comfort
com + motion = commotion com + lection = collection
de + motion = demotion ex + lection = election
ad + cent = accent com + laborate = collaborate
re + cent = recent ex + laborate = elaborate
ad + cess = access com + rosion = corrosion
re + cess = recess ex + rosion = erosion

1. Look at the two words in each pair. Do they have the same root? _____
Do they have the same prefix? _____ Do both words contain a double consonant when the prefix and root are joined? _____
2. Write the three words in which a double consonant results without any change in the spelling of the prefix.
____________   _____________  _____________
3. How many words have double consonants caused by an assimilated prefix that has been changed to match the first letter of the base word or root? _____

Lesson Generalization

Some double consonants occur because the last letter of the prefix is the same as the first letter of the base word or root: misstated.

Most double consonants occur because the prefix is assimilated. The last letter of the prefix changes to match the first letter of the base word or root:
ad + cent = accent.

Mnemonic device: Associating the words in each pair will help you to remember that one of the double consonants belongs to the prefix, and one belongs to the root or base word.


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