What Are Interrogative Adjectives? 4 Common Mistakes

What are interrogative adjectives? These three words can be tricky to use well, but this guide will help.

The English language has many adjectives that add color and interest to your writing. These descriptive words can also help create sentence structure and differentiate between different items in a sentence or paragraph. One of these types of adjectives is the interrogative adjective.

Interrogative adjectives ask a question when they modify a noun or pronoun. Though they often start interrogative, they can appear in other parts of the sentence. This guide will help you understand these words and use them well.

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What Are Interrogative Adjectives?

The interrogative adjectives are the adjectives that form questions. English grammar has three of them, and they are: which, whose and what.

Using Interrogative Adjectives in a Question

The primary way that interrogative adjectives appear in English sentences is in questions. These adjectives start interrogative sentences and show the reader that the sentence is, in fact, a question. Here are some examples:

  • Whose house is hosting the garage sale? (Whose modifies house)
  • Which brand of milk do you prefer? (Which modifies brand)
  • What ice cream do you want for dessert? (What modifies ice cream)

Indirect Questions and Interrogative Adjectives

Many questions start with a question word, such as an interrogative adjective, and end in a question mark. However, some sentences have indirect questions in the middle and do not follow this structure. Interrogative adjectives can show these types of indirect questions. Here is an example:

  • I don’t know whose house that is.

“Whose” modifies “house” in this indirect question, even though the sentence is a declarative sentence, not an interrogative one.

Using Interrogative Adjectives

Each of the three interrogative adjectives has its specific use. The easiest one to remember is “whose.” This question word is a possessive adjective, and you use it in questions of possession. For instance:

  • Whose car is parked in the handicapped spot?

In this question, the person wants to know who owns the car.

“What” and “which” can be harder to differentiate. “What” is a word you use when options are unknown, while “which” is used when you do know the options. Here are some examples:

  • What entree would you like? (In this example, using “what” means that there are many options, and you do not know which ones the person is choosing between.)
  • What color is the dress? (In this example, the speaker does not know any color choices, so the potential choices are nearly endless.)
  • Which entree would you like, chicken or beef? (In this example, there are only two available choices.)
  • Which color is the dress? (In this choice, the speaker implies that they know the choices the person was looking at when choosing a dress.)

The Question of Interrogative Determiners

Question words like “which,” “what,” and “whose” can be used in many different parts of speech, not just adjectives. For this reason, some grammar guides call them interrogative determiners instead of interrogative adjectives. This term does not change how the words work in the sentence. It is simply another term for the same set of words.

Common Mistakes with Interrogative Adjectives

Interrogative adjectives are simple, but they can be a source of confusion for many learning English grammar. Here are some common mistakes to watch for.

Mistake 1: Confusing Interrogative Adjectives with Interrogative Pronouns

One common mistake English learners make is confusing Interrogative adjectives with interrogative pronouns. This confusion is expected because the words are the same. The way the words are used in the sentence changes their part of the speech.

If an interrogative word is being used as a pronoun, it will not have a noun that it modifies. For example:

  • Which is a good day to meet for coffee?
  • Whose should I use?
  • What are you going to choose?

In each of these sentences, the first word of the sentence is a pronoun because it does not have a word it modifies.

Changing the sentence slightly turns them into interrogative adjective examples, as in the following sentences:

  • Which day is a good one to meet for coffee?
  • Whose art piece should I use?
  • What dessert are you going to choose?

These sentences have the same basic meaning, but they change the beginning words into adjectives by adding a noun for them to modify.

Mistake 2: Interrogative Adjectives Considered Comparative or Superlative Adjectives

What are interrogative adjectives
Interrogative adjectives are never superlative or comparative adjectives

Interrogative adjectives are never superlative or comparative adjectives. You cannot say that something is the “what-est” of them all or is “which-er” than another.

Mistake 3: Confusing Interrogative Adjectives with Interrogative Adverbs

Interrogative adjectives constantly modify nouns, pronouns, or noun phrases. They cannot modify adverbs, verbs, or other adjectives. They also cannot modify a verb phrase.

However, interrogative adverbs are easy to confuse with their adjective counterparts. These are “why,” “where,” “how,” and “when.” The answers to these questions are verbs or adverbs, making them interrogative adverbs.

Mistake 4: Misspelling Whose

“Whose” is the interrogative or possessive adjective form of the pronoun “who.” It can also be a relative pronoun, which allows it to start a clause within the sentence. Some people mistakenly spell it “who’s.”

“Who’s” is the conjunction form of the verb phrase “who is” or “who has.” “Whose” and “who’s” are two different words, and you need to spell them correctly for the proper use.

How to Use Interrogative Adjectives in Your Next Essay

While questions are not a standard sentence structure in an essay, they sometimes have a place. Sometimes, interrogative adjectives make sense to start these sentences. If using the words “whose,” “which,” or “what,” make sure the noun or pronoun you are modifying is outlined in the sentence, and use the correct question word for the sentence structure.

Using these words accurately will allow you to craft essays with proper grammar that make your point well.

If you are interested in learning more, check out our guide on the difference between past and present verbs!