por sí sola

by herself

→ por
phrase Rare #39,239
by herself Used for a female person doing something without help; also means on her own or alone.
SP: Mi hermana resolvió el problema por sí sola.
EN: My sister solved the problem by herself.

Nancy no podía mover el escritorio por sí sola.

Nancy couldn't move the desk by herself.

Mi abuela vive por sí sola.

My grandmother lives on her own.

Ella fue allá por sí sola.

She went there on her own.

Suele hacerlo por sí sola.

She usually does it on her own.

Ella es incapaz de hacer nada por sí sola.

She is incapable of doing anything on her own.

De ese modo, el agua corría colina abajo por sí sola.

That way, the water flowed downhill on its own.

— El manantial de las colinas (1986)