Questions & Answers about Wir kaufen die Tische und die Stühle.
Wait, I thought die was for feminine nouns. Why is it used for Tische and Stühle?
die is the definite article for all plural nouns, no matter what their gender is in the singular! Both der Tisch (the table) and der Stuhl (the chair) are masculine, but they use die here because they are plural.
How did Tisch become Tische?
Why does Stühle have an umlaut (ü) when the singular is Stuhl?
Why does the verb kaufen end in -en here?
Because the subject is wir (we). When you use wir, the verb almost always stays in its original dictionary form, ending in -en.