Learn Dutch: Aanstaande zaterdag is het toneelstuk helemaal uitverkocht. - This coming Saturday, the play is completely sold out.

In Dutch, you can use the simple present tense to talk about the future, as long as there is a clear time word that shows it hasn't happened yet. Here, the time phrase Aanstaande zaterdag (This coming Saturday) makes the future context clear, so the present tense is works perfectly instead of a future tense like zal zijn.

Why is the verb is placed before the subject het toneelstuk?

Because the sentence starts with the time phrase Aanstaande zaterdag. Dutch uses the V2 rule, meaning the conjugated verb must be in the second position of the sentence. Since the time phrase takes up the first position, the verb is must come second, pushing the subject het toneelstuk to the third position.

What exactly does aanstaande mean, and does it change endings like a normal adjective?

Aanstaande means upcoming or next. While it is technically an adjective, in fixed time expressions it almost always keeps the -e ending regardless of the noun's gender. You will see aanstaande zaterdag, aanstaande vrijdag, and frequently even aanstaande weekend (though aanstaand weekend is the strictly correct form for a het-word).

Is uitverkocht a verb or an adjective here?