"I was at his house last month."
Translation:Estuve en su casa el mes pasado.
Why does there need to be "el" ? I still don't understand why definite articles need to be used before other words when I thought it could just be "Estuve en su casa mes pasado."
When ¨pasado¨ is used (and comes after the time noun like month, year, etc), think of ¨pasado¨ as meaning ¨that has passed.¨ So ¨el mes pasado¨ is ¨the month that has passed¨ in English. It could not be just ¨month that has passed.¨ I hope this helps with remembering! (and I realize that you posted 2 months ago, so if you don´t need this anymore, congrats!)
Just to let you know I appreciate your answer even though it was directed to the past. It helps todays
A su casa = to his house (ex: I went to his home) En su casa = in his house (ex: I was at his home)
Estaba and estuve are both accepted here. Correct me if I'm wrong, but;
Would "estaba" imply that the speaker was there for the whole month, i.e. spent the whole month living there, while "estuve" would imply that he was there once or some miscellaneous number of times during the last month?
'Last month' gives us a specific time, so it is 100% preterite. To make it imperfect u should change last month for something like every month, every week, often, never,always, occasionally ( for awhile), at that times ( times used ambiguously), etc.