Educational worksheet teaching the use of the suffix "-er" to form nouns indicating a person who performs an action, with examples and exercises.

Problem Explanation:

The worksheet is about understanding and applying suffixes, specifically the suffix "-er", which is added to verbs to form nouns. The suffix "-er" typically indicates:

1. Someone who does something.
2. Something that does something.
3. Someone who provides or is involved with something.

The task is to fill in the blanks by adding the suffix "-er" to the given verbs to form the appropriate nouns.

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Solution:

#### Step-by-Step Analysis and Filling in the Blanks:

1. Someone who rides is a _______
- Verb: "rides"
- Add "-er": "rider"
- Answer: rider

2. Someone who teaches is a _______
- Verb: "teaches"
- Add "-er": "teacher"
- Answer: teacher

3. Someone who practices law is a _______
- Verb: "practices"
- Add "-er": "practitioner"
- Note: While "practicer" could be formed, the standard term is "practitioner."
- Answer: practitioner

4. Someone who follows is a _______
- Verb: "follows"
- Add "-er": "follower"
- Answer: follower

5. Someone who leads is a _______
- Verb: "leads"
- Add "-er": "leader"
- Answer: leader

6. Someone who jokes is a _______
- Verb: "jokes"
- Add "-er": "joker"
- Answer: joker

7. Someone who listens is a _______
- Verb: "listens"
- Add "-er": "listener"
- Answer: listener

8. Someone who writes is a _______
- Verb: "writes"
- Add "-er": "writer"
- Answer: writer

9. Someone who reads is a _______
- Verb: "reads"
- Add "-er": "reader"
- Answer: reader

10. Someone who sits is a _______
- Verb: "sits"
- Add "-er": "sitter"
- Answer: sitter

11. Someone who walks is a _______
- Verb: "walks"
- Add "-er": "walker"
- Answer: walker

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Final Answers:

1. rider
2. teacher
3. practitioner
4. follower
5. leader
6. joker
7. listener
8. writer
9. reader
10. sitter
11. walker

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Boxed Final Answer:

\[
\boxed{
\begin{array}{ll}
1. & \text{rider} \\
2. & \text{teacher} \\
3. & \text{practitioner} \\
4. & \text{follower} \\
5. & \text{leader} \\
6. & \text{joker} \\
7. & \text{listener} \\
8. & \text{writer} \\
9. & \text{reader} \\
10. & \text{sitter} \\
11. & \text{walker} \\
\end{array}
}
\]