COULD - COULD NOT

We use could to talk about what was possible in the past, what we were able or free to do:

• I could swim when I was 5 years old.
• My grandmother could speak seven languages.
• When we arrived home, we could not open the door. (...couldn't open the door.)
• Could you understand what he was saying.

We use could (positive) and couldn't (negative) for general ability in the past.

CLICK HERE to practice!