Students practice identifying correct auxiliary verbs by completing sentences about a character named Carol and her pizza cooking attempts.

Let's solve each sentence in the "Auxiliary Verbs" worksheet step by step. The goal is to choose the correct auxiliary verb (helping verb) to complete each sentence correctly.

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1. Carol _______ learned to make pizza.

- A. have
- B. has
- C. will

✔ Correct answer: B. has

Explanation:
"Carol" is a singular subject, so we use "has" (not "have").
The phrase "has learned" is present perfect tense, which indicates an action that started in the past and may continue into the present.
So: Carol has learned to make pizza.

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2. Her brother _______ try anything once.

- A. was
- B. were
- C. will

✔ Correct answer: C. will

Explanation:
This sentence expresses a future intention or willingness.
"Will try" means he is willing or plans to try something.
"Was" and "were" are past tense and don't fit here.
So: Her brother will try anything once.

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3. Some of Carol’s pizzas _______ tasted rubbery.

- A. was
- B. have
- C. has

✔ Correct answer: B. have

Explanation:
"Some of Carol’s pizzas" is plural, so we need a plural auxiliary verb.
"Have" agrees with plural subjects. "Has" is for singular.
"Was" is incorrect because it's not a helping verb for this structure.
We're talking about multiple pizzas that have tasted rubbery — past experience affecting the present.
So: Some of Carol’s pizzas have tasted rubbery.

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4. She _______ vowed this one will be good.

- A. were
- B. have
- C. has

✔ Correct answer: C. has

Explanation:
"Vowed" is a past tense verb. The sentence needs a helping verb before it.
"She has vowed" = she made a promise in the past.
"Has" is used with singular subjects ("she") in present perfect tense.
"Were" doesn't work here; "have" would require plural subject.
So: She has vowed this one will be good.

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5. Her brother _______ tasting it right now.

- A. are
- B. is
- C. will

✔ Correct answer: B. is

Explanation:
"Her brother" is singular → requires "is".
"Is tasting" is present continuous tense, showing an action happening now.
"Are" is for plural subjects. "Will" refers to future, not current action.
So: Her brother is tasting it right now.

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6. He _______ biting, but nothing _______ happening.

- A. is
- B. can
- C. am

✔ Correct answer: A. is (first blank), and A. is (second blank)

But wait — only one choice per question? Let's look again.

Actually, this question has two blanks, but the options are:

- A. is
- B. can
- C. am

This seems like a mistake in formatting. But logically, the sentence is:

> He _______ biting, but nothing _______ happening.

So both blanks need verbs.

Let’s analyze:

- First blank: "He ___ biting" → Present continuous → is biting
- Second blank: "nothing ___ happening" → "Nothing" is treated as singular → is happening

So both blanks should be "is".

But since only one option is given per question, likely the intended answer is:

✔ A. is (for both blanks, though the format is odd)

Alternatively, if the question expects only one choice, then A. is is the best choice for both.

So:
He is biting, but nothing is happening.

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7. Carol really _______ not make a decent pizza.

- A. could
- B. have
- C. can

✔ Correct answer: C. can

Explanation:
"Can" expresses ability.
"Carol really can not make a decent pizza" = she lacks the skill.
"Could" is past or hypothetical — less direct.
"Have" doesn’t work grammatically here.
So: Carol really can not make a decent pizza.

(Note: "cannot" is often written as "can't", but "can not" is also acceptable.)

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✔ Final Answers:

1. B. has
2. C. will
3. B. have
4. C. has
5. B. is
6. A. is (and implied second blank also "is")
7. C. can

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Summary:

| Question | Answer |
|--------|--------|
| 1 | B. has |
| 2 | C. will |
| 3 | B. have |
| 4 | C. has |
| 5 | B. is |
| 6 | A. is |
| 7 | C. can |

These choices correctly use auxiliary verbs based on subject-verb agreement, tense, and meaning.