A caballo regalado no se le mira el colmillo

Spanish: &#039;El coche que me regaló mi tío es viejo, pero ya sabes, a caballo regalado no se le mira el colmillo.&#039;
English: &#039;The car my uncle gave me is old, but you know, don&#039;t look a gift horse in the mouth.&#039;

This phrase literally translates to 'Don't check the teeth of a gift horse.' It is used to express that one should not criticize or be ungrateful for a gift or opportunity they have received, even if it's not perfect.