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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