What Grammar Is The Word Is? | Meaning And Usage Rules

You’ve seen “is” a million times. Still, it can feel slippery when you try to label its grammar on a worksheet, in a lesson plan, or while editing your own writing. That’s because is wears a few different hats. The trick is to judge it by the job it’s doing in the sentence, not by the word itself.

This guide gives you a fast way to classify “is,” plus a set of sentence tests you can reuse. If your topic is what grammar is the word is?, you’ll leave with labels that match common school grammar terms and with “why” that makes sense in real writing.

Fast map Of what “is” can be

Before you start tagging parts of speech, it helps to know the main roles “is” can play. Use this table as your quick map, then use the tests in the next sections to pick the right label for your sentence.

Role “Is” plays	Pattern you’ll see	How to label it
Linking verb (copula)	Subject + is + noun/adjective	Main verb; linking verb
Main verb of being	Subject + is + place/time/state	Main verb
Auxiliary for progressive	is + verb-ing	Auxiliary (helping) verb
Auxiliary for passive	is + past participle	Auxiliary (helping) verb
Existential “there is”	There + is + noun	Main verb; often taught as “be” verb
Clause opener in clefts	It is + X + that/who…	Main verb; linking verb
Fixed phrases	That is, as is, what is…	Verb form; label by the sentence role
Elliptical answers	Yes, it is. / It is.	Main verb; “be” verb

What Grammar Is The Word Is? Quick Classification Steps

When a teacher, rubric, or test asks this, they usually want two pieces: (1) what word class it belongs to, and (2) what function it has in that sentence. The word class is easy: “is” belongs to the verb family as a form of “be.” The function is the part that changes.

Step 1: Find what comes after “is”

Read three words past “is.” That tiny window often tells you the label.

• If you see a noun or adjective next, “is” often links the subject to a description or identity.
• If you see an -ing form next, “is” often helps build the present progressive.
• If you see a past participle next (often ending in -ed, -en, or irregular), “is” often helps build the passive voice.

Step 2: Ask “Can I swap in ‘are/was/were’?”

If the sentence stays grammatical when you change tense or number (is → are/was/were), you’re dealing with the verb “be” doing standard verb work. This doesn’t finish the label, but it confirms you’re in the right zone.

Step 3: Decide whether “is” carries the main meaning

Try this quick check: if you remove the word after “is,” does the sentence collapse?

• Linking/main verb use: “The soup is hot.” Remove “hot” and you’re left with “The soup is,” which feels unfinished in normal writing.
• Auxiliary use: “The soup is simmering.” Remove “simmering” and “The soup is” still feels unfinished, yet the bigger clue is that “simmering” is the action verb and “is” helps with tense/aspect.

“Is” as a linking verb

In school grammar, the most common label you’ll see is linking verb. Linking verbs connect the subject to a subject complement, which is a noun phrase or an adjective phrase that describes or identifies the subject.

How to spot a linking “is”

Use this test: replace the complement with a different description. If the structure still works and you’re still describing the same subject, “is” is acting as a link.

• “Mina is tired.” → “Mina is alert.”
• “That building is a museum.” → “That building is an office.”

What label to write on homework

If you get one blank and it says “part of speech,” write verb. If it asks “type of verb,” write linking verb or copular verb (copula is the grammar term for a linking “be”). If it asks “predicate,” the noun/adjective after “is” is often called a predicate nominative (noun) or a predicate adjective (adjective).

“Is” as a main verb of being

Not every “is” links to an identity or description. Sometimes it simply states existence, location, or a state in a plain way.

Common patterns

• Location: “The keys are on the table.” In singular: “The key is on the table.”
• Time: “It is noon.”
• Status/state: “The server is down.”

Many classrooms still group these under “linking verb” because they don’t take a direct object and they connect the subject to a phrase that completes the idea. If your course splits them, you can call “is” the main verb and label the following phrase as a complement (often an adverbial or prepositional phrase).

“Is” as an auxiliary verb

When “is” teams up with another verb, it often functions as an auxiliary (also called a helping verb). In that setup, the next verb carries the action meaning while “is” carries tense and supports the construction.

Present progressive: “is” + verb-ing

Use this label when the sentence describes an action in progress around the present time.

• “She is studying.”
• “The baby is sleeping.”

Passive voice: “is” + past participle

Use this label when the subject receives the action, or when the sentence is built to focus on the result rather than the doer.

• “The tickets are sold.” In singular: “The ticket is sold.”
• “The window is broken.”

If you want a clean, reliable reference for “be” forms and common uses, the Cambridge Dictionary grammar page on “be” lays out core patterns and terminology in plain language.

The “there is” pattern

“There is” and “there are” can confuse students because “there” looks like a place word, yet it’s working as a dummy subject that introduces the real subject later in the sentence.

What’s the real subject?

In “There is a problem,” the real subject is “a problem.” You can prove it by switching to plural: “There are problems.” The verb agrees with the noun that comes after it.

What to call “is” here

It’s still a form of “be,” still a verb, and in most school labels it’s treated as a main verb. If your worksheet asks “helping or main,” mark it as main because it isn’t supporting another verb form.

How to label “is” in real sentences

Here are quick, reusable tests that keep you from guessing. Run them in order. Stop when one gives you a clear match.

Test A: Look for another verb right after it

If “is” is followed by a verb form (-ing or past participle), “is” is usually auxiliary.

• “is running” → auxiliary + present participle
• “is repaired” → auxiliary + past participle

Test B: Try swapping “is” with “seems”

If “seems” fits without changing the core meaning too much, “is” is acting as a linking verb.

• “The plan is risky.” → “The plan seems risky.”
• “The plan is in the folder.” → “The plan seems in the folder.” (doesn’t work)

Test C: Ask “What is being asserted?”

If the sentence asserts an identity or description, label “is” as linking. If it asserts an action in progress or a passive construction, label “is” as auxiliary.

For classroom-friendly wording on verb types, the Purdue OWL page on verb tenses is a solid anchor for tense and verb-form discussions.

Contracted forms and punctuation

“Is” often appears as a contraction. The grammar label doesn’t change just because the apostrophe shows up.

Contractions you’ll see

• it’s = it is
• she’s = she is
• there’s = there is
• what’s = what is

A common trap: “its” vs “it’s”

“It’s” is always “it is.” “Its” is possessive. A quick check: if you can expand it to “it is,” you need the apostrophe.

Why “is” is not a preposition or pronoun

This sounds basic, yet it’s a real source of mix-ups when students try to label every word in a sentence. “Is” can sit next to prepositional phrases (“is in the bag”), but that doesn’t make it a preposition. It can sit next to pronouns (“is she ready?”), but that doesn’t make it a pronoun. It stays a verb form of “be.” The words around it change its function, not its word class.

Sentence types that make “is” feel tricky

Some structures hide the role of “is” because the sentence is doing something extra: emphasis, inversion, or ellipsis.

Cleft sentences: “It is X that…”

In “It is Alex who called,” the sentence puts a spotlight on “Alex.” “Is” links “it” to the focused element. You can still label “is” as a linking verb.

Questions: word order flips

In “Is the dog hungry?” the verb comes first. It’s still the same verb role you’d see in the statement “The dog is hungry.” Label it the same way: linking verb (or main “be” verb) depending on your course labels.

Short answers: the rest is implied

In conversation, we often answer with “It is.” The missing words are understood from context. In grammar terms, “is” still acts as the verb, and the complement is just omitted in the reply.

Common classroom labels and what they mean

Teachers don’t all use the same set of terms. Here’s how the labels usually line up.

• Verb / be verb: broad label for “is” as a verb form.
• Linking verb: “is” connects subject to a complement (noun/adjective phrase).
• Helping verb / auxiliary: “is” supports another verb form in progressive or passive.
• Copula: grammar term for a linking “be.”
• Predicate nominative/adjective: names for the complement after linking “is.”

If you’re writing an answer to what grammar is the word is? on a quiz, a safe two-part response is: “It’s a verb (a form of ‘be’); in this sentence it functions as a linking verb/auxiliary verb.” That matches how most rubrics award points.

Editing moves that fix “is” heavy writing

Grammar questions often turn into writing questions. Too many “is” sentences can sound flat, even when they’re correct. You don’t need to ban “is.” You just need options.

Swap in a stronger verb when you mean an action

“The solution is on the table” is fine if location is the point. If you mean a change or action, pick a verb that says it.

• Flat: “The numbers are on the page.”
• Clearer: “The numbers appear on the page.”

Turn some predicate adjectives into verbs

“The room is silent” describes a state. If you want motion or mood, you can often reshape the sentence.

• State: “The crowd is quiet.”
• Action: “The crowd quiets down.”

Keep “is” when clarity is the goal

Definitions, math statements, and direct identifications often read best with “is.” If the sentence is doing clean explanatory work, let it.

Quick error table for “is” in student writing

This table targets the mistakes that show up a lot in assignments: agreement, contractions, tense mixing, and passive confusion.

Slip	What it looks like	Fix
Subject-verb mismatch	“The results is clear.”	“The results are clear.”
Singular “there is” with plural noun	“There is many reasons.”	“There are many reasons.”
Its/it’s mix-up	“Its raining.”	“It’s raining.”
Unclear passive	“The rule is followed.”	“Students follow the rule.”
Tense clash in a paragraph	“He is tired and went home.”	“He was tired and went home.”
Double verb form	“She is goes to school.”	“She goes to school.”
Overuse of “is” in descriptions	“The essay is good. It is clear.”	Mix verbs: “The essay reads clearly.”

One-page checklist for labeling “is”

If you want a clean routine you can use under time pressure, run this checklist on any sentence that contains “is.”

1. Look right after “is.” If you see verb-ing, label “is” as auxiliary for progressive.
2. If you see a past participle, label “is” as auxiliary for passive.
3. If you see a noun or adjective that renames or describes the subject, label “is” as a linking verb.
4. If you see “there is/there’s,” treat “is” as the main “be” verb and make it agree with the noun after it.
5. If the sentence is a question, flip it back to statement order to label it.

Used this way, “is” stops being confusing. It’s a single verb form with a few common jobs, and the sentence tells you which job it’s doing.