Overview of Adding Suffixes that Change Base Words’ Final y to i

There are two sections in this resource:

Overview of Adding Suffixes that Change Base Words’ Final y to i
Video Demonstration

The estimated time to complete this resource is 15 minutes.

You may download and print the following documents by clicking the links below.

Lesson Plan
Lesson Materials
Word List
Video Transcript

When the final y of a base word is preceded by a consonant, the y changes to an i when a suffix is added, regardless of whether the suffix begins with a vowel or a consonant.

Teach students the final y rule: If a base word ends in consonant-y, change the y to i before adding the suffix.

The suffix -es is added to a base word ending in consonant-y, rather than the suffix -s, as in puppy puppies and city cities.

The final y does not change when the suffix begins with i (e.g., ing, ish) because doing so would create an awkward spelling (e.g., study becomes studying, not studiing). Teach this exception after students have mastered the final y rule. When initially teaching this concept, do not include examples with -ing or -ish suffixes.

The i usually retains the sound of the y in the base word. For example, in marry and married, both the y and i make the long e sound; in cry and cries, both the y and i make the long i sound. There are a few exceptions, however, such as happily, plentiful, and easily.

Video Demonstration

This video demonstrates how to teach students to read and spell words in which the final y of the base is changed to i when a suffix is added.

Please find the Suffix Math handout for part of this video. The handout may also be downloaded from the RELATED ITEMS section below, or you may use the materials packet download from the Overview section at the beginning of this resource.

Click play on the video when you're ready to begin.


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