Ability
Can someone do it?
Merkitys
Ability tells us what someone can do, whether learned or not. It covers learned skills as well as what someone's body or mind allows them to do. Languages express it with helper verbs, endings, or ordinary phrases, and some have no special form for it. Unlike Permission, Ability concerns what someone can do, not what they are allowed to do.
Näin tunnistat sen
Check whether the message says someone has the skill or capacity to do something, rather than merely being allowed to do it.
Opiskeltavalla kielelläsi
English commonly expresses ability with can followed by a verb without to. Could often describes general ability in the past, while was/were able to usually describes success on one occasion. Be able to also allows forms such as will be able to for future ability.
I can ride a bike.
Can expresses a skill, and ride follows without to.
When I was ten, I could swim across the pool.
Could describes an ability the speaker had at that age, not one particular swim.
The door was stuck, but we were able to open it.
Were able to shows that opening the door succeeded on this occasion.
Learners whose language marks the second verb in ability phrases may add to after can or could. Learners whose language uses one form for both general past ability and success on one occasion may overuse could.