In Spanish, the forms tuyo(a), suyo(a) and vuestro(a) require a definite article in the singular and in the plural when they are the subject of the phrase.
1. tuyo(a) (sustantivo masculino o femenino)(of one person) (singular); tuyos(as) (m,fpl)(plural); suyo(a) (sustantivo masculino o femenino)(formal: singular); suyos(as) (m,fpl)(formal: plural)
my house is big but yours is bigger mi casa es grande, pero la tuya/suya es mayor
this book is yours este libro es tuyo/suyo
these books are yours estos libros son tuyos/suyos
a friend of yours un amigo tuyo/suyo
where's that brother of yours? ¿dónde anda ese hermano tuyo?
yours (sincerely/faithfully) atentamente
2. vuestro(a)(of more than one person) (singular) (español de España), suyo(a) (Am or); vuestros(as) (español de España), suyos(as) (Am or)
this book is yours (Formal) (plural)(Formal) este libro es vuestro/suyo
these books are yours estos libros son vuestros/suyos
1(belonging to one person)(familiar)(referring to singular possession)(el/la) tuyoatuya;atuya(referring to plural possession)(los/las) tuyosastuyas;astuyas
is that box yours?¿esa caja es tuya?;I've lost my pen, can I use yours?he perdido el bolígrafo, ¿puedo usar el tuyo?;that dog of yours!¡ese perro tuyo!;which is yours?¿cuál es el tuyo?;these are my keys and those are yoursestas son mis llaves y esas son las tuyas;what's yours?(offering drink)¿qué vas a tomar?
(referring to singular possession)(el/la) suyoasuya;asuya(el/la) de usted;(referring to plural possession)(los/las) suyosassuyas;assuyas(los/las) de usted
you and yoursusted y los suyos;is that box yours?¿esa caja es suya?;I've lost my pen, can I use yours?he perdido el bolígrafo, ¿puedo usar el suyo?;these are my keys and those are yoursestas son mis llaves y esas son las suyas;Yours(in letter)le saluda atentamente
2(belonging to more than one person)(familiar)(referring to singular possession)(el/la) vuestroavuestra;avuestra(el/la) suyoasuya;asuya(LAm)(el/la) de ustedes; (LAm)(referring to plural possession)(los/las) vuestrosasvuestras;asvuestras(los/las) suyos asas;asas(LAm)(los/las) de ustedes; (LAm)
that's yourseso es vuestro
(referring to singular possession)(el/la) suyoasuya;asuya(el/la) de ustedes;(referring to plural possession)(los/las) suyosassuyas;assuyas(los/las) de ustedes;
