"Do you work on Sunday?"
Translation:¿Tú trabajas el domingo?
Guys, just like French, Spanish also puts articles behind the days of the week
Français: "Travaillez vous le Dimanche?"
Español: "Trabaja (usted) el domingo?
I know this might be confusing for someone learning a Romance language for the first time, bur that's how it's done in Spanish, French, Italian, etc.
So if "Trabajas el domingo?" was correct before why do I need to put Tu in front of Trabajas if I already know that Trabajas or the "as" at the end refers to "you" and in question form means" do you"? Isn't Tu trabajas saying you twice? Wouldn't that translate to "You do you work on Sunday?"
See this on Questions in Spanish: https://www.thoughtco.com/upside-down-punctuation-in-spanish-3080317
"lunes" is both singular and plural, there is no such word as "lun" or "lune", so if you want to specify just the one Monday or multiple Mondays, you'll have to rely on the article "el" or "los".
The word for Sunday does have seperate singular and plural forms, and the article must match: "el" for "domingo" and "los" for "domingos"
"Los" is only used for plural nouns, did you forget? It would have been correct if the sentence used "Sundays"/"domingos".
EDIT: Looking back, I see where you got confused. In Spanish, the five weekdays, "lunes" through "viernes" are all both singular and plural at the same time. There is no "lune" or "marte" or "miercol", if you get what I mean. "Sabado" and "domingo" on the other hand do have seperate singular and plural forms.
Yes, always for "The"; no, never for "your"; and well-yes-but-actually-no for "on".
"El" is "the" plain and simple. If you want to say "your" you use Spanish's possessive adjective "tu".
As for "on", the word always transliterates to "en". The complicating part is that where we English speakers would use the positional preposition "on/en" to mark what day we do something ("work on Sonday"), Spanish speakers would use the definite article "the/el" instead ("work the Sunday").