I have one question. When do I include definite articles? For example, I translated the sentence to "Tu hermano bebe EL agua." When are definite articles appropriate? I had thought a rule of them was overuse instead of underuse them.
The English sentence DL is stating is a, singular, brother, so simply 'tu hermano bebe' is correct for DL. The plural form I used was not acceptable in this instance but meant as an example of what is would look like when 'tus' is used in answer to Jontona's question.