acabas de banarte means: just swim
"Acabas de hacer" in Spanish means "you have just done" in English. It refers to an action that was recently completed.
"Lo acabas de hacer"
It means: "You just made"
It means: "What nonsense did you just write"
Sé un poco de español, pero no sé lo que acabas de decir.
Yo había estado + participle I have been + participle for example: I have been reading. Yo había estado leído If you mean the question 'What have you been up to?' Que acaba usted/acabas de hacer?
The indefinite article "de" in Spanish is analogous to the indefinite article "of" in English.
de means of in spanish
De.
Trienta de octubre translates from Spanish to mean the 30th of October.
de que: from what
De = from. Para = to.