An infinitive is a verb in its base form, often with “to,” that can act like a noun, an adjective, or an adverb inside a sentence.
If you’ve ever paused mid-sentence and wondered, “Should I write to go or going?” you’re not alone. Infinitives sit in the middle of many English choices, and small changes can shift meaning, tone, or grammar.
This article gives you clean, copy-ready sentences you can borrow. You’ll see what an infinitive looks like, where it shows up, and how to avoid the mistakes that trip up even strong writers.
What An Infinitive Is And Why It Shows Up So Often
An infinitive is built from a verb’s base form. Many infinitives use to + base verb: to study, to speak, to remember. Some infinitives drop to; those are often called “bare infinitives,” as in can swim or must leave.
Infinitives matter because they let you name actions without turning them into full clauses. That makes sentences smoother and more direct. You can use an infinitive to state a purpose, express an intention, or connect two ideas without extra words.
Two Fast Ways To Spot An Infinitive
- Look for “to” + verb: “to write,” “to ask,” “to solve.”
- Check after a modal: can, could, may, might, must, shall, should, will, would + base verb (no “to”).
That’s the form. Next comes the part that makes infinitives useful: the job they do in a sentence.
Example Of Infinitive In A Sentence With Clear Patterns
Below are sentences you can lift into essays, emails, and everyday writing. Read each one and ask, “What is the infinitive doing here?” That one question turns a fuzzy topic into something you can control.
Infinitive As A Noun
When an infinitive acts as a noun, it can sit in subject or object position. It often answers “what?” in a clean, compact way.
- Subject:To learn takes patience.
- Subject with dummy “it”: It helps to plan before you start.
- Object: She decided to apply early.
- Object after a question word: I don’t know what to say.
Infinitive As An Adjective
An infinitive can modify a noun, often giving a sense of “that you can…” or “that you should…”. These are common in academic writing because they pack detail into a short space.
- We have homework to finish tonight.
- He’s the right person to ask.
- There’s nothing to fear in that chapter.
- She brought a book to read on the bus.
Infinitive As An Adverb
When an infinitive acts as an adverb, it often answers “why?” or “for what purpose?” It can also describe a result or an attitude.
- We met early to review the outline.
- He whispered to avoid waking the baby.
- She grew up to become a teacher.
- I was relieved to hear the news.
Infinitive Phrase With Its Own Object
Many infinitives arrive with a mini “package” attached: objects, modifiers, or complements. That whole package is an infinitive phrase.
- They agreed to split the cost.
- He promised to call after class.
- She tried to write a stronger thesis.
- We need to finish this draft today.
How To Pick The Right Infinitive Form In Real Writing
Most mistakes come from one of three spots: verb patterns, the choice between to and bare form, and word order inside the phrase. If you watch those three, your infinitives will feel natural.
To-Infinitive Versus Bare Infinitive
The to-infinitive is common after many main verbs: want, decide, hope, plan, agree, learn, promise. The bare infinitive shows up after modal verbs (can, must, should) and after a few structures like make and let.
If you want the official grammar framing in plain language, Cambridge’s notes on “Infinitives with and without to” spell out the two forms and where they tend to appear.
When An Infinitive Needs A Subject
Sometimes the infinitive has its own “doer.” English often marks that doer with for: for + noun/pronoun + to + verb.
- It’s hard for me to focus in a noisy room.
- She arranged for the tutor to visit on Friday.
- There’s time for you to revise before the test.
Where To Place Adverbs Inside The Infinitive
Writers get nervous about lines like “to quickly finish.” You’ll hear the term “split infinitive” for cases where a word slips between to and the verb. In modern English, this is often fine when it keeps meaning clear.
Try these three options and pick the one that reads clean in your sentence:
- Before the infinitive: She decided quickly to leave.
- Between “to” and the verb: She decided to quickly leave before the rain.
- After the infinitive phrase: She decided to leave quickly.
Rule of thumb: keep the adverb close to what it changes. If moving it shifts meaning, keep it where it does the job.
Common Infinitive Roles You Can Copy
Use the table below as a menu. Pick the role you need, then swap in your own verb and details. Don’t reread it like a textbook; treat it like sentence building blocks.
| Pattern | What It Does | Model Sentence |
|---|---|---|
| To + verb (noun as subject) | Names an action | To practice daily builds fluency. |
| It + be + adj + to + verb | Makes a judgment | It’s smart to check your sources. |
| Verb + to + verb | Links intention to action | They hope to travel in June. |
| Noun + to + verb (adjective use) | Modifies a noun | I need a place to study tonight. |
| To + verb (purpose) | Shows why | She called to confirm the time. |
| Too + adj + to + verb | Shows a limit | The text was too small to read. |
| Adj + enough + to + verb | Shows sufficiency | He was calm enough to respond. |
| For + noun + to + verb | Adds a doer | It helps for students to take notes. |
| Wh-word + to + verb | Builds an indirect question | Tell me where to submit the file. |
Infinitive Versus Gerund In One Sentence Choice
English lets you say “I like to read” and “I like reading.” Both can work, yet they don’t always feel the same. In many cases, the difference is about meaning or habit, not grammar error.
When Meaning Changes
Some verbs shift meaning depending on whether you use a gerund or an infinitive. Here are a few pairs that writers bump into often:
- Stop: “He stopped to talk” (he paused in order to talk) vs “He stopped talking” (he ended the talking).
- Remember: “Remember to lock the door” (don’t forget) vs “I remember locking the door” (memory of a past action).
- Try: “Try to restart the app” (make an effort) vs “Try restarting the app” (test a method).
Purdue OWL’s page on infinitives sits alongside its gerund material, which helps when you’re choosing the right form in mixed sentences.
Verbs And Structures That Commonly Take Infinitives
Many learners memorize long verb lists, then freeze when a new verb shows up. A better move is to learn clusters: verbs of intention, verbs of decision, verbs of effort, and a small set of exceptions that take the bare form.
| Verb Or Structure | Form After It | Model Sentence |
|---|---|---|
| want, plan, hope | to-infinitive | I plan to finish the reading. |
| decide, agree, promise | to-infinitive | They agreed to meet at noon. |
| learn, manage, fail | to-infinitive | She managed to solve the puzzle. |
| ask, tell, invite (someone) | object + to-infinitive | He told me to bring my notes. |
| make, let (someone) | object + bare infinitive | The coach made us run laps. |
| modal verbs (can, must, should) | bare infinitive | You should call your advisor. |
| help | to-infinitive or bare infinitive | She helped me (to) edit the essay. |
| question words (what, how, where) | wh-word + to-infinitive | He explained how to format the paper. |
Mistakes That Make Infinitives Sound Off
Most infinitive errors don’t look dramatic. They just make a sentence feel clunky or unclear. Here are fixes you can apply fast.
Mixing Two Patterns By Accident
Writers sometimes stack patterns like “I suggested him to go.” In standard English, suggest does not take an object + to-infinitive in that way. Cleaner options:
- I suggested that he go.
- I suggested going.
Using “To” After A Modal
Modal verbs take the bare form, so “must to leave” and “can to swim” sound wrong. Write “must leave” and “can swim.”
Dangling Purpose Phrases
A purpose infinitive should match the subject. If you write “To get a higher grade, the rubric was printed,” the sentence suggests the rubric is trying to get a grade. Fix it by putting the doer in front:
- To get a higher grade, I printed the rubric.
A Mini Practice Set With Answers
Try these on paper or in a notes app. After each one, label the infinitive as noun, adjective, or adverb. Then check the answers.
- To travel alone takes planning.
- She found a topic to write about.
- We stayed late to finish the lab report.
- It was hard for him to admit the mistake.
- Tell me how to cite the article.
Answer List
- 1: noun (subject)
- 2: adjective (modifies “topic”)
- 3: adverb (purpose of staying)
- 4: infinitive phrase with its own doer (“for him”)
- 5: noun phrase after a question word (“how to cite”)
A Simple Checklist Before You Hit Submit
- Can you spot the base verb inside the infinitive?
- Does the verb before it normally take a to-infinitive, a gerund, or the bare form?
- If there’s a purpose phrase, does it match the subject doing the action?
- If you moved an adverb, would the meaning change?
- Read the sentence once out loud. If it feels stiff, try a different placement of the infinitive phrase.
Once you get used to these patterns, infinitives stop feeling like a rule set and start feeling like a set of options you can choose from on purpose.
References & Sources
- Cambridge Dictionary.“Infinitives with and without to.”Explains the two infinitive forms and where each one is used.
- Purdue OWL.“Infinitives.”Breaks down infinitive structure and common patterns in academic writing.