Lesson 28 The prefix ex

ex + pect	= expect	ex + cuse	= excuse
ex + pired	= expired	ex + clamation	= exclamation
ex + pert	= expert	ex + cursion	= excursion
ex + perience	= experience
ex + pensive	= expensive	ex + fort	= effort
		ex + fective	= effective
ex + tremely	= extremely	ex + ficiency	= efficiency
ex + tension	= extension
ex + tinguish	= extinguish	ex + lection	= election
ex + terior	= exterior	ex + levate	= elevate
ex + tinct	= extinct	ex + scape	= escape
		ex + vaporate	= evaporate

1.	In how many words is the prefix ex added to a root that begins with the letter p? _____ with the letter t? _____ with the letter c? _____ Does the spelling of the prefix change when it is joined to these roots? _______
2.	Is the letter x ever followed by the letters s or z? _____
3.	In how many words does the spelling of the prefix change to match the first letter of a root? _____ What is that letter? _____
4.	How does the spelling of the prefix change in the last four words? ________________________________________________________

Lesson Generalization Unlike the "Mad ad, " the prefix ex seldom loses its identity. It causes few doubling problems because the letter x is never doubled and seldom changes to match the first letter of the root. ex remains ex before roots that begin with p, t, or c. ex changes to ef when joined to the roots that begin with the letter f. ex changes to e before most other consonants. The challenge in spelling words that begin with the prefix ex are caused by the s sound of the letter x. Do not add the letter s between the prefix and the root.

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