missing 'to' after 'able'

Many writers drop the small word to after able and write phrases like "able run" instead of "able to run." The rule is simple: when able is followed by a verb that names an action, use the infinitive marker to.

Quick answer

Use able + to + base verb. Do not use able + bare verb in standard English.

Correct: He is able to finish the report.
Incorrect: He is able finish the report.
If you spot able immediately followed by a verb, insert to between them.

Core explanation

Able is an adjective that pairs with an infinitive: able to + base verb. The to marks the verb that expresses the action someone can perform. Omit it and the sentence sounds like a typo or nonstandard phrasing.

Incorrect: She is able climb the ladder.
Correct: She is able to climb the ladder.

Use be able to when you need tense or aspect that can versus cannot cover (e.g., past: she was able to, future: she will be able to). For many present-general statements, can is a shorter alternative (she can climb), but be able to is required for some constructions and clarifies ability in past or specific situations.

Why writers make this mistake

The error usually comes from listening to the phrase in speech, typing fast, or overrelying on instinct. Spoken contraction and casual rhythm can hide the missing to, so it slips into writing.

Sound-based guessing: the phrase sounds fine aloud.
Typing fast: small words get lost in drafts.
Pattern confusion: mixing up similar structures like able + adjective or capable of + -ing.

How it sounds in real writing (work, school, casual)

Seeing correct forms in typical contexts helps the rule stick. Below are natural sentences that show how to use able to across situations.

Work: The team is able to deploy the update overnight if we approve the patch.
Work: She will be able to present the results at tomorrow's meeting.
Work: We're able to reduce costs by renegotiating the contract.
School: He was able to finish the lab write-up before the deadline.
School: Students are able to access the reading list online.
School: The group was able to solve the problem after several attempts.
Casual: I'm able to pick you up after work.
Casual: Are you able to join us for dinner?
Casual: They'll be able to fix the bike by Saturday.

Wrong vs right examples you can copy

These side-by-side pairs highlight the missing to and give clean corrections you can reuse.

Wrong: He is able run a marathon without stopping.
Right: He is able to run a marathon without stopping.
Wrong: The team is able finish the project on time.
Right: The team is able to finish the project on time.
Wrong: I was able do the repair myself.
Right: I was able to do the repair myself.
Wrong: Are you able attend the meeting tomorrow?
Right: Are you able to attend the meeting tomorrow?
Wrong: She's able handle customer calls this afternoon.
Right: She's able to handle customer calls this afternoon.
Wrong: They'll be able arrive by noon.
Right: They'll be able to arrive by noon.

How to fix your own sentence (rewrite help)

Fixing this error can be as simple as inserting to, but sometimes a cleaner rewrite improves clarity and tone. Follow these steps:

Identify what you mean (ability now, in the past, or in the future).
Insert to: able to + base verb.
Reread for tone; consider using can, will be able to, or a different verb if it sounds stiff.

Original: This plan is able work if everyone stays late.Fix: This plan is able to work if everyone stays late.
Rewrite: This plan will work if everyone stays late.
Original: The assignment feels able finish now.Fix: The assignment feels able to finish now.
Rewrite: I feel able to finish the assignment now.
Original: Is that able pick up the package today?Fix: Is that able to pick up the package today?
Rewrite: Can you pick up the package today?

A simple memory trick

Picture able and the action as a unit: able to + verb. If you can replace the phrase with can or be able to in the same tense, the structure is probably correct. Training your eye on real sentences helps more than rote rules.

When you see able followed by a verb, mentally insert to and read the sentence aloud.
Search your drafts for able and fix every instance at once to reinforce the habit.

Similar mistakes to watch for

Spacing, hyphenation, and small prepositions cause related errors. A quick scan for patterns saves time.

capable of + -ing (not capable to do)
ready to (not ready-to unless part of a hyphenated modifier with careful rewrites)
avoid unnecessary hyphens: able to is two words
watch verb-form confusion after adjectives (e.g., able to vs able + adjective)

FAQ

Is "able run" ever correct?

No. Standard English requires able + to + base verb when able precedes an action. Write "able to run."

Can I use "can" instead of "be able to"?

Often yes for simple present ability (she can swim). Use be able to when you need past/future tense, emphasis on a specific achievement, or a construction that doesn't accept can (e.g., He was able to finish the task then).

Should I hyphenate "able to" as "able-to"?

Generally no. "Able to" stays as two words. Avoid hyphenation unless you're creating a deliberate compound modifier and then consider rephrasing for clarity.

How do I quickly find missing "to" errors in a document?

Search for the word able and scan the word that follows. If the next word is a base verb (finish, run, attend), insert to. Reading sentences aloud catches many instances.

What other adjectives commonly cause confusion?

Adjectives like capable (use capable of + -ing), prepared (prepared to), and ready (ready to) each pair with specific patterns. Learn each pattern and watch for the missing preposition or infinitive marker.

Quick proofreading habit (soft CTA)

Before sending an important message or submitting work, scan for able + verb and apply the three-step fix (find able → insert to if needed → read aloud). A short, focused pass prevents this common slip and keeps your writing crisp.