no sabía nadar

No sabía nadar demasiado bien.

I couldn't swim very well.

Mary decía que no sabía nadar bien.

Mary said that she didn't know how to swim well.

Mary dijo que no sabía nadar bien.

Mary said she didn't know how to swim well.

No sabía nadar y no tenía chaleco salvavidas.

I didn't know how to swim, and I didn't have a life jacket.

¿Quién te dijo que yo no sabía nadar?

Who told you I couldn't swim?

Y yo no sabía nadar.

And I didn’t know how to swim.

— Roma (2018)

Él no sabía nadar.

He didn't know how to swim.