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"All day" is a phrase which is often translated as "todo el día", and "any day" is a phrase which is often translated as "cualquier día". Learn more about the difference between "all day" and "any day" below.
all day( 
al
dey
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
b. el día entero 
I've been working on this project all day.Llevo trabajando en este proyecto el día entero.
any day( 
eh
-
ni
dey
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
a. cualquier día 
Which day of the week shall we meet again? - Any day next week is fine.¿Cuál día de la semana nos volvemos a ver? - Cualquier día de la semana que viene está bien.