Introduce: The Prefixes in-, im-, il- and ir-
What to Do
Write the prefixes in-, im-, il-, and ir- on the board or on a piece of chart paper for the students to see.
1. Introduce the prefixes in-, im-, il-, and ir- and solicit examples of words that contain in-, im-, il-, and ir-.
Today we are going to learn about prefixes. Who knows what a prefix is?
2. Allow time for students to respond.
A prefix is a word part added to the beginning of a word. It changes the meaning of a word. in-, im-, il-, and ir- are prefixes that are used in many words. Incorrect, immature, illogical, and irrational are all words that have the prefixes in-, im-, il-, and ir- in them. Do you know of any other words that have the prefixes in-, im-, il-, and ir-?
3. As students share, write the responses on the board or on a piece of chart paper. Circle the prefixes in-, im-, il-, and ir- in each word as it is given.
4. Define the meaning of in-, im-, il-, and ir-, as well as words containing the prefixes in-, im-, il-, and ir-.
Look at the list of words with the prefixes in-, im-, il-, and ir-. Who knows what in-, im-, il-, and ir- mean? in-, im-, il-, and ir- mean “not.” Look at incorrect. Incorrect means “not correct.” When the prefix in- is added to correct, it changes the meaning of the word. Can anyone tell us what immature means? What about illogical and irrational?
5. Solicit the meanings of the remaining words from the first step.
6. Connect words to students’ prior knowledge. Ask students a variety of questions to help them connect their experiences to the words in the list generated in the first step. For example:
How many incorrect answers did you have on the assignment?
Do you think Teddy was being immature when he cut in line?
Does this argument seem illogical to you?
Can anyone use irrational in a sentence?
For Advanced Students:
Encourage these students to use each word on the class-created list in a sentence.
Explain how the parts of speech may change when a prefix is added. In the case of the prefixes in-, im-, il-, and ir-, however, both the root word and the word with the prefix added are adjectives.
For Struggling Students:
For the students who have difficulty understanding what a prefix is, try presenting the word list above as a series of math equations. For example:
- in + correct = incorrect
- im + mature = immature
- il + logical = illogical
- ir + rational = irrational
For ELL Students:
Point out that some of the same prefixes may exist in their native language. If the prefix is not the same as in English, there may be an equivalent in their native language.