Learn French: Participent-ils à la nouvelle émission ? - Are they participating in the new show?

This is called subject-verb inversion, which is a formal way to ask a question in French. You simply swap the subject pronoun (ils) and the verb (participent) and connect them with a hyphen.

Do I pronounce the "t" in participent-ils?

Yes! Usually, the -ent ending on French verbs is completely silent. However, when you invert the verb and a pronoun starting with a vowel (like ils), you pronounce the "t" to connect the words. It sounds like "par-tee-seep-teel".

Why is the word à used here?

In French, the verb participer (to participate) must always be followed by the preposition à when you are saying what someone is participating in. You cannot just say participer la nouvelle émission.

Why does nouvelle come before émission? Don't French adjectives usually go after the noun?

Most French adjectives do go after the noun, but nouvelle (new) is an exception. It belongs to a small group of common adjectives that describe Beauty, Age, Number, Goodness, or Size (often remembered as the "BANGS" rule) which almost always come before the noun.