You can respond to it in a couple of ways:
1. Ask for the word or phrase they want to translate:
* "¿Qué quieres decir en español?" (What do you want to say in Spanish?)
* "¿Cuál es la palabra o frase que quieres traducir?" (What is the word or phrase you want to translate?)
2. Provide a direct translation:
* "Tell me the word or phrase, and I'll tell you how to say it in Spanish."
3. Explain the process of translation:
* "To tell you how to say something in Spanish, I need to know what you want to translate. "
Remember to be polite and helpful. You can also offer to help them learn more Spanish if they're interested.