Able (adjective) — having the necessary skill, knowledge, or opportunity to do something. Almost always used in the phrase be able to followed by a base infinitive: With practice, you will be able to speak fluently.
What Does Able Mean?
Able entered Middle English in the 14th century from Old French able or hable, which came from Latin habilis meaning "easy to handle" or "apt", from habere (to hold, to have). The same Latin root gave English the suffix -able (as in readable, manageable) and the related noun ability.
In modern British English, able is used in two main ways. First, predicatively in the structure be able to + infinitive, which expresses capability across all tenses and moods where the modal verb can cannot go — for example in future, perfect, and infinitive constructions. Second, attributively before a noun to describe a competent or talented person: an able diplomat, the most able student in the group.
Understanding when to use be able to rather than can is one of the most practical grammar points for intermediate learners. The rule of thumb: wherever can has no form (infinitive, perfect, future), use be able to instead.
Example Sentences
| Sentence | Level | Usage note |
|---|---|---|
| With practice, you will be able to speak fluently. | A2 | be able to in future tense (cannot use will can) |
| She was able to finish the report before the deadline. | B1 | was able to for a single successful past action |
| He has never been able to understand why she left. | B1 | have been able to in present perfect |
| I would like to be able to travel without restrictions. | B2 | be able to after a modal + infinitive construction |
| Only the most able candidates were shortlisted for the final round. | C1 | attributive use — able as a pre-nominal adjective meaning "talented" |
Common Collocations
| Collocation | Example |
|---|---|
| be able to | Are you able to attend the meeting? |
| highly able | She is a highly able researcher. |
| more able | Tasks were differentiated for more able pupils. |
| most able | The prize went to the most able student. |
| perfectly able | He is perfectly able to make his own decisions. |
| fully able | She was fully able to understand the risks. |
| able-bodied | The programme is open to all able-bodied volunteers. |
| well able | You are well able to handle this yourself. |
| able and willing | We need staff who are able and willing to work flexible hours. |
| an able speaker / manager | She proved herself an able manager during the crisis. |
Usage Notes
Able vs. can: Both be able to and can express present ability, but only be able to works in all tenses. Use can for general present ability or informal speech. Use be able to in future constructions (will be able to), perfect constructions (has been able to), and after other modals (might be able to, should be able to).
Was able to vs. could: For a specific, single past achievement, prefer was/were able to rather than could. Compare: She could swim (general past ability) vs. She was able to swim across the lake (one specific occasion). Using could for a single successful past event sounds unnatural in affirmative sentences.
Attributive use: When used before a noun (an able assistant, an able-bodied athlete), able has a formal or literary tone. In everyday speech, capable, skilled, or talented are more common alternatives.
Common Mistakes
Watch Out For
I able to speak Spanish.
I am able to speak Spanish. (Always use the verb be before able to.)
She will can drive next year.
She will be able to drive next year. (Two modals cannot combine — use be able to instead.)
He was able to swim when he was a child. (general past ability)
He could swim when he was a child. (Use could for general or repeated past ability, not was able to.)