"He has arrived at seven every day to work in the field."

[Sam_uk]

Todos os dias is accepted but todo dia is not??

[Paulenrique]

that should be accepted!

[JohnGrunewald]

How about "cada dia" which seems right to me?

[ChelseaBurns]

That's the question I have—what is the distinction between "cada dia" and "todo dia"?

[Danmoller]

"Cada dia" is like focusing each day one by one. It doesn't work very well for this sentence, unless you really want to focus that individual days, one by one idea....it fits better sentences where each day has something new, like "a cada dia ele chega mais tarde" (he is getting later and later every day).

"Todo dia" is simply every day.

[ChelseaBurns]

Thanks for the clarification—that's a big help!