8.3: Doubling the final consonant

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Have you ever noticed that sometimes when adding a suffix the last letter in the base word will double and sometimes it does not double? The structure of many of the words used in the Robert Frost poem lend themselves to investigating the doubling convention.

Activity

First, read and enjoy the poem. Then go back to the poem and look at the highlighted words. Can you determine the base words and the prefixes and suffixes?

Examine the words in the charts below and see if you can figure out the patterns for doubling and not doubling.

“Acquainted with the Night”

I have been one acquainted with the night.

I have walked out in rain—and back in rain.

I have outwalked the furthest city light.

I have looked down the saddest city lane.

I have passed by the watchman on his beat

And dropped my eyes, unwilling to explain.

I have stood still and stopped the sound of feet

When far away an interrupted cry

Came over houses from another street,...

Proclaimed the time was neither wrong nor right.

I have been one acquainted with the night.

Words not doubled	Word sum	Base word	Pattern from the vowel
walked outwalked	walk+ed out+walk+ed	walk	VCC
looked	look+ed	look	VVC
passed	pass+ed	pass	VCC
unwilling	un+will+ing	will	VCC
interrupted	inter+rupt+ed	rupt	VCC
proclaimed	pro+claim+ed	claim	VVC

Words doubled	Word sum	Base word	pattern from the vowel
stopped	stop(p)+ed	stop	VC
saddest	sad(d)+est	sad	VC
dropped	drop(p)+ed	drop	VC

When a one syllable base word ends with a single vowel and a single consonant (VC) and you add a vowel suffix such as -ing, -ed, -er, -est, the final consonant will double. The words from the Frost poem stopped, saddest, dropped are all examples of this convention. When a base word ends with a vowel and two consonants (VCC) or two vowels and a consonant (VVC), the final letter will not double when adding a vowel suffix.

A group of curious 5th graders in Marybeth Stevens’ classroom wanted to understand why the plural of bus is buses and not busses. Read how the students with the help of Marybeth investigated if the word buses was an exception to the doubling convention in her blog “Is this the Right Bus?’ https://mbsteven.edublogs.org/2019/12/09/is-this-the-right-bus/