where do you put a comma in have you chosen what you are going to wear on opening night?

In this?

have you chosen what you are going to wear on opening night?

If that's what you're working on, there needs to be a capital H on the first word and no comma anywhere.

In the given sentence, a comma should be placed after the introductory phrase "have you chosen". Therefore, the correct punctuation would be: "Have you chosen, what you are going to wear on opening night?"

To determine where to place a comma in a sentence, it is helpful to understand the basic principles of comma usage. Here are a few scenarios where commas are typically used:

1. To separate items in a series: "I bought apples, bananas, and oranges."
2. To separate independent clauses in a compound sentence: "I walked to the park, and my sister rode her bike."
3. To set off introductory elements: "After the rain stops, we can go outside."
4. To separate nonessential elements: "John Smith, the CEO of the company, will be attending the meeting."
5. To separate coordinate adjectives: "It was a long, exhausting day."

In the given sentence, "have you chosen" serves as an introductory element, and a comma is needed to separate it from the rest of the sentence.