subject + am/is/are + able + to + verbPresent ability with be able to. Choose am, is, or are from the subject.
Be Able To
A2Be able to expresses ability in tenses where can does not work. Change be for time, add not for negatives, and move be for questions.
What you'll learn
- Use be able to for past, future, and perfect ability.
- Choose the right form of be before able to.
- Build negatives with not after be.
- Ask questions by moving be before the subject.
- Keep to before the main verb after able.
- Recognize time markers that pair with be able to.
Structure
subject + was/were + able + to + verbPast ability. Choose was or were from the subject.
subject + will + be + able + to + verbFuture ability uses will be able to, not will can.
subject + be + not + able + to + verbPut not after be. Keep to before the main verb.
Be/Will + subject + able + to + verb + ?Questions start with be or will. Do not add do.
Build a sentence
Subject
Verb
Hewillbeabletocome
He will be able to come tomorrow.
Future ability uses will be able to, not will can.
When to use
Future ability
Use will be able to for ability in the future. Maria will be able to drive next year.
Past ability or result
Use was able to / were able to for ability or successful action in the past. Tom was able to find the key.
Ability up to now
Use has been able to / have been able to when the time connects to now. Lisa has been able to work from home since May.
Markers
yesterdaylast yeartomorrowsoonnext monthsince then
Common mistakes
Wrong
Maria will can drive next year.
Correct
Maria will be able to drive next year.
After will, use be able to for future ability. Can does not go after will.
Wrong
Tom has can finish the task.
Correct
Tom has been able to finish the task.
After has or have, use been able to. Can does not follow have.
Wrong
We were able finish on time.
Correct
We were able to finish on time.
Able is followed by to + base verb.
Wrong
Do you are able to help tonight?
Correct
Are you able to help tonight?
Questions with be able to start with be, not do.
Wrong
Anna is able not to join us today.
Correct
Anna is not able to join us today.
For simple negative ability, put not after be: is not able to.
Common misconceptions
❝ I can use can in any tense if the meaning is ability. ❞
Can is limited. For many tense patterns, English uses be able to instead.
❝ Because able to is not can, negatives need do not. ❞
Be able to already has be, so make the negative with not after be: is not able to, was not able to.
Skills in this rule (6)
USE_FOR_OTHER_TENSESw5Use be able to when can does not fit the tense
Use be able to to talk about ability in past, future, perfect, and other forms where can is not used. Change be, not able to.
CHANGE_BE_FOR_TIMEw5Change be to match the subject and time
Use am, is, are, was, were, be, or been before able to. The form of be shows the time and matches the subject.
NEGATIVE_WITH_NOTw4Make negatives with not after be
Put not after the form of be: is not able to, was not able to, will not be able to. Keep able to together with the main verb.
QUESTION_WITH_BEw5Ask questions by moving be before the subject
In questions, put the form of be before the subject: Are you able to...?, Was he able to...?, Will they be able to...?. Do not add do or can.
KEEP_TO_BEFORE_VERBw4Keep to before the main verb
After able, use to + base verb: able to swim, able to solve, able to come. Do not drop to and do not add -ing here.
MARKERS_FOR_TIMEw3Use time words that show when the ability happens
Words like yesterday, tomorrow, soon, and since then help show the time with be able to. They often appear when you move beyond simple present ability.