Prefix, Root Word, Suffix worksheet for students to practice word analysis.

Task: Identify the prefix, root word, and suffix of each word in the list.

#### Definitions:
- Prefix: A group of letters added to the beginning of a word to change its meaning.
- Root Word: The base part of a word that carries the primary meaning.
- Suffix: A group of letters added to the end of a word to change its meaning or form.

#### Solution:

| WORDS | PREFIX | ROOT WORD | SUFFIX |
|---------------|----------|--------------|------------|
| preheat | pre- | heat | |
| unkind | un- | kind | |
| undersea | under- | sea | |
| submarine | sub- | marine | |
| comfortable | comfort | able | -able |
| wonderful | wonder | ful | -ful |
| defrost | de- | frost | |
| overlook | over- | look | |
| quickly | quick | ly | -ly |
| breathless | breath | less | -less |
| tallest | tall | est | -est |
| replay | re- | play | |
| underground | under- | ground | |
| small | | small | |
| unhappy | un- | happy | |
| preschool | pre- | school | |
| disappear | dis- | appear | |
| inside | in- | side | |
| reread | re- | read | |

Explanation:

1. preheat:
- Prefix: "pre-" (meaning "before").
- Root Word: "heat" (the main part of the word).
- Suffix: None.

2. unkind:
- Prefix: "un-" (meaning "not").
- Root Word: "kind" (the main part of the word).
- Suffix: None.

3. undersea:
- Prefix: "under-" (meaning "below").
- Root Word: "sea" (the main part of the word).
- Suffix: None.

4. submarine:
- Prefix: "sub-" (meaning "under").
- Root Word: "marine" (the main part of the word).
- Suffix: None.

5. comfortable:
- Prefix: None.
- Root Word: "comfort" (the main part of the word).
- Suffix: "-able" (meaning "capable of being").

6. wonderful:
- Prefix: None.
- Root Word: "wonder" (the main part of the word).
- Suffix: "-ful" (meaning "full of").

7. defrost:
- Prefix: "de-" (meaning "remove").
- Root Word: "frost" (the main part of the word).
- Suffix: None.

8. overlook:
- Prefix: "over-" (meaning "above").
- Root Word: "look" (the main part of the word).
- Suffix: None.

9. quickly:
- Prefix: None.
- Root Word: "quick" (the main part of the word).
- Suffix: "-ly" (indicating an adverb).

10. breathless:
- Prefix: None.
- Root Word: "breath" (the main part of the word).
- Suffix: "-less" (meaning "without").

11. tallest:
- Prefix: None.
- Root Word: "tall" (the main part of the word).
- Suffix: "-est" (indicating superlative form).

12. replay:
- Prefix: "re-" (meaning "again").
- Root Word: "play" (the main part of the word).
- Suffix: None.

13. underground:
- Prefix: "under-" (meaning "below").
- Root Word: "ground" (the main part of the word).
- Suffix: None.

14. small:
- Prefix: None.
- Root Word: "small" (the main part of the word).
- Suffix: None.

15. unhappy:
- Prefix: "un-" (meaning "not").
- Root Word: "happy" (the main part of the word).
- Suffix: None.

16. preschool:
- Prefix: "pre-" (meaning "before").
- Root Word: "school" (the main part of the word).
- Suffix: None.

17. disappear:
- Prefix: "dis-" (meaning "away").
- Root Word: "appear" (the main part of the word).
- Suffix: None.

18. inside:
- Prefix: "in-" (meaning "within").
- Root Word: "side" (the main part of the word).
- Suffix: None.

19. reread:
- Prefix: "re-" (meaning "again").
- Root Word: "read" (the main part of the word).
- Suffix: None.

Final Answer:

\boxed{
\begin{array}{|c|c|c|c|}
\hline
\text{WORDS} & \text{PREFIX} & \text{ROOT WORD} & \text{SUFFIX} \\
\hline
\text{preheat} & \text{pre-} & \text{heat} & \text{} \\
\hline
\text{unkind} & \text{un-} & \text{kind} & \text{} \\
\hline
\text{undersea} & \text{under-} & \text{sea} & \text{} \\
\hline
\text{submarine} & \text{sub-} & \text{marine} & \text{} \\
\hline
\text{comfortable} & \text{} & \text{comfort} & \text{-able} \\
\hline
\text{wonderful} & \text{} & \text{wonder} & \text{-ful} \\
\hline
\text{defrost} & \text{de-} & \text{frost} & \text{} \\
\hline
\text{overlook} & \text{over-} & \text{look} & \text{} \\
\hline
\text{quickly} & \text{} & \text{quick} & \text{-ly} \\
\hline
\text{breathless} & \text{} & \text{breath} & \text{-less} \\
\hline
\text{tallest} & \text{} & \text{tall} & \text{-est} \\
\hline
\text{replay} & \text{re-} & \text{play} & \text{} \\
\hline
\text{underground} & \text{under-} & \text{ground} & \text{} \\
\hline
\text{small} & \text{} & \text{small} & \text{} \\
\hline
\text{unhappy} & \text{un-} & \text{happy} & \text{} \\
\hline
\text{preschool} & \text{pre-} & \text{school} & \text{} \\
\hline
\text{disappear} & \text{dis-} & \text{appear} & \text{} \\
\hline
\text{inside} & \text{in-} & \text{side} & \text{} \\
\hline
\text{reread} & \text{re-} & \text{read} & \text{} \\
\hline
\end{array}
}