English · B1 · verb · 5 minutes
Could: possibility and conditional ability
Use could + base verb for less certain options, past general ability, or polite requests.
Understand the choice
Could is deliberately flexible. At age six I could swim is past general ability; We could leave now is an option; Could you help? is a softened request.
Core rule: Could is unchanged and takes a bare infinitive; its interpretation comes from past time, hypothetical context, or request form.
Notice it in context
We could take the earlier train if the meeting ended on time.
Podríamos tomar el tren anterior si la reunión terminara a tiempo.
Could take presents an option; if + ended gives the hypothetical condition.
When she was five, she could read simple stories.
At age five she had the general ability to read easy stories.
Past-time context selects general ability.
Could you send me the revised draft?
Please send me the changed version, if possible.
Question form creates a polite request rather than asking ability literally.
What to remember
- For one successfully completed past event, managed to/was able to is often clearer than could.
- Could not contracts to couldn’t and can express inability or impossibility.
Common trap: Do not add to after modal could: could take, not could to take.