Prefixes worksheet with a train theme, featuring exercises to practice adding prefixes to words and forming sentences.

Problem Overview:

The task involves adding prefixes to base words to create new words. The prefixes provided are dis-, un-, and in-. These prefixes change the meaning of the base word, often negating or reversing its original meaning.

#### Step 1: Understand the Prefixes
- Dis-: Often used with verbs and adjectives to indicate reversal or opposite action (e.g., "dislike," "disappear").
- Un-: Typically used with adjectives and nouns to negate their meaning (e.g., "undo," "unhappy").
- In-: Usually used with adjectives to indicate the absence or lack of a quality (e.g., "inactive," "incorrect").

#### Step 2: Solve Each Part

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Part A: Add the Correct Prefix to Each Base Word

We need to add the appropriate prefix to each base word to form a new word.

1. able
- Prefix: un-
- New Word: unable
- Explanation: "Unable" means not able to do something.

2. pleased
- Prefix: dis-
- New Word: displeased
- Explanation: "Displeased" means not pleased or unhappy.

3. respect
- Prefix: dis-
- New Word: disrespect
- Explanation: "Disrespect" means showing a lack of respect.

4. open
- Prefix: un-
- New Word: unopen
- Explanation: While "unopen" is not a standard word, it can be interpreted as "not open." A more common alternative might be "closed," but based on the instruction, "un-" is appropriate here.

5. correct
- Prefix: in-
- New Word: incorrect
- Explanation: "Incorrect" means not correct or wrong.

6. active
- Prefix: in-
- New Word: inactive
- Explanation: "Inactive" means not active or not engaged in activity.

7. honest
- Prefix: un-
- New Word: unhonest
- Explanation: While "dishonest" is more commonly used, "unhonest" is also valid in some contexts. However, for consistency, we'll use "dishonest."

8. comfortable
- Prefix: un-
- New Word: uncomfortable
- Explanation: "Uncomfortable" means not comfortable.

9. possible
- Prefix: im- (Note: Although "im-" is not listed, it is a variant of "in-" and is commonly used with words starting with "p.")
- New Word: impossible
- Explanation: "Impossible" means not possible.

10. happy
- Prefix: un-
- New Word: unhappy
- Explanation: "Unhappy" means not happy.

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Part B: Use the Words You Made Above to Complete Each Sentence

Now, we will use the newly formed words to complete the sentences.

1. Romeo tries to copy his sister's homework, but she could not _______ him.
- Word: dislike
- Sentence: Romeo tries to copy his sister's homework, but she could not dislike him.

2. She did not _______ her friend's invitation because she was going for a run.
- Word: accept
- Sentence: She did not accept her friend's invitation because she was going for a run.

3. Gloves do not _______ everyone.
- Word: fit
- Sentence: Gloves do not fit everyone.

4. Paul wanted to _______ on his project.
- Word: complete
- Sentence: Paul wanted to complete on his project.

5. Jack had no _______ at the park today.
- Word: luck
- Sentence: Jack had no luck at the park today.

6. India would never _______ another country.
- Word: invade
- Sentence: India would never invade another country.

7. Use the broom even though it is _______.
- Word: broken
- Sentence: Use the broom even though it is broken.

8. Jim felt the weather was _______.
- Word: unpleasant
- Sentence: Jim felt the weather was unpleasant.

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Final Answer:

#### Part A:
1. unable
2. displeased
3. disrespect
4. unopen
5. incorrect
6. inactive
7. dishonest
8. uncomfortable
9. impossible
10. unhappy

#### Part B:
1. Romeo tries to copy his sister's homework, but she could not dislike him.
2. She did not accept her friend's invitation because she was going for a run.
3. Gloves do not fit everyone.
4. Paul wanted to complete on his project.
5. Jack had no luck at the park today.
6. India would never invade another country.
7. Use the broom even though it is broken.
8. Jim felt the weather was unpleasant.

Final Answer:
\boxed{
\text{See above for detailed solutions.}
}