Learn German: Der Kunde erhält den Ansatz gefärbt. - The customer gets his roots dyed.

In an active sentence, the customer is the receiver of the action and takes the dative case: Jemand färbt dem Kunden den Ansatz (Someone dyes the roots for the customer). The Recipient Passive lets us make that receiver the subject of the sentence. The dative dem Kunden turns into the nominative der Kunde, and we use the helper verb erhalten combined with the past participle gefärbt.

Why use erhält instead of bekommt or kriegt here?

All three verbs mean "to get" or "to receive" and can form the Recipient Passive. Kriegen is highly informal and mostly spoken. Bekommen is the standard, everyday choice. Erhalten is the most formal of the three. Using erhält makes this sentence sound like a formal, professional description of a salon service.

Why is Ansatz singular when the English translation says "roots"?

In German hairdressing vocabulary, der Ansatz refers to the new hair growth at the scalp as a single collective area or "base". While English speakers talk about dyeing their "roots" in the plural, Germans refer to dyeing the singular Ansatz.

Why is den Ansatz in the accusative case here?

Even though the sentence is passive, den Ansatz remains the direct object of the action, just as it would be in the active version of the sentence. The Recipient Passive promotes the dative object to the nominative subject, but it leaves the accusative object exactly as it is.