1. Decoding/ Word Analysis Structural Analysis: Suffixes –ous, -eous, -ious
5th Grade
Lesson 18

2. Did you notice that the root word is right and the suffix is -eous?
Look at the word below and read it to yourself. Read it out loud when I point to it
righteous
Turn and tell your partner how many syllables this word has and where it should be divided.
Now, turn and tell your partner the root word and the suffix.
Did you notice that the root word is right and the suffix is -eous?

3. Now, turn and tell your partner the root word and the suffix.
Look at the word below and read it to yourself. Read it out loud when I point to it
wondrous
Turn and tell your partner how many syllables this word has and where it should be divided.
Now, turn and tell your partner the root word and the suffix.
Did you notice that the root word is wonder and the suffix is -ous? Notice that in this word, the spelling of the root word changed when the suffix was added.

4. Now, turn and tell your partner the root word and the suffix.
Look at the word below and read it to yourself. Read it out loud when I point to it
nauseous
Turn and tell your partner how many syllables this word has and where it should be divided.
Now, turn and tell your partner the root word and the suffix.
Did you notice that the root word is nausea and the suffix is -eous? Notice that in this word, the spelling of the root word changed when the suffix was added.

5. Now, turn and tell your partner the root word and the suffix.
Look at the word below and read it to yourself. Read it out loud when I point to it
victorious
Turn and tell your partner how many syllables this word has and where it should be divided.
Now, turn and tell your partner the root word and the suffix.
Did you notice that the root word is victory and the suffix is -ious? Notice that in this word, the spelling of the root word changed when the suffix was added.

6. –eous and –ious can be pronounced as either /əs/ OR /e/ əs/
-----ous is usually pronounced /əs/ and
–eous and –ious can be pronounced as either /əs/ OR /e/ əs/

7. glorious glor/i/ous nervous nerv/ous courteous court/e/ous studious
Let’s try it with a few more words. Look at each of the words below, and with your partner find the root word and the suffix. Then blend them together to read the word
glorious
nervous
courteous
studious
glor/i/ous
nerv/ous
court/e/ous
stu/di/ous
Did you notice that sometimes the root word’s spelling changes when a suffix is added? For example, the root word of glorious is glory, but the final y must be dropped before adding –ious.

8. Try it on your own
With your partner look through your science or social studies book for 3 words that have the suffixes –ous, -eous, and –ious. Write the words you find , divide them into syllables, and then blend the syllables to pronounce the words.