1 (close) they are very attached (to each other) se quieren mucho; to be attached to (fond of) [+person] tener cariño a; [+theory] estar apegado a; to become attached to sb encariñarse con algn
2 to be attached (married, spoken for) no estar libre
3 (associated) the salary attached to the post is ... el sueldo que corresponde al puesto es ...; to be attached to an embassy estar agregado a una embajada; commission attached to the Ministry of ... comisión que depende del Ministerio de ...