When you refer to “your foot,” you would use a singular tu pie. When you refer to “your feet,” you would use the plural, tus pies. wher appropriate, masculine and feminine pronouns apply.
Yo – I
Él /ella – he/she
Ellos, ellas – they
Nosotros – we
Tú – you (informal)
Usted – you (formal)
Me – (to) me
Te – (to) you
Le – (to) him, her, you
Les – (to) them
Nos – (to) us, ourselves
Mi(s) – my
Tu(s) – your
Su(s) – her, his, yours (formal)
Nuestro(s), nuestra(s) – our(s)