us

1 (as direct object) : nos <they were visiting us : nos visitaban>
2 (as indirect object) : nos <he gave us a present : nos dio un regalo>
3 (as object of preposition) : nosotros, nosotras <stay with us : quédese con nosotros> <both of us : nosotros dos>
4 (for emphasis) : nosotros <it's us! : ¡somos nosotros!>