This is the 13944th most frequent Spanish word.
sostenerse
"To sustain oneself, remain standing, or stay valid."
In this sentence, 'sostenerse' is used to mean 'to remain standing' or 'to maintain one's position physically.'
El edificio logró sostenerse durante el terremoto.
The building managed to stand firm during the earthquake.
Here, 'sostenerse' refers to 'to maintain oneself or the business' in a financial or operational sense.
Para sostenerse en el negocio, es necesario adaptarse a las demandas del mercado.
To sustain oneself in business, it is necessary to adapt to market demands.
The usage in this instance implies 'to uphold' or 'to remain steadfast in one's ideals or beliefs.