Lesson 179: Che, Che Cosa, and Cosa -- They all mean 'what'?

Che, Che cosa, and Cosa are all interrogatives that mean, what, and while sometimes they are interchangeable, this is not always the case.

Let's look at some guidelines:

1. Che is both an interrogative pronoun and an interrogative adjective, while Che cosa and Cosa are only interrogative pronouns:
   
   Che macchina vuoi comprare?
   What car do you want to buy?
   
   Che cosa macchina vuoi comprare? = WRONG
   Cosa macchina vuoi comprare? = WRONG
   
   
2. Che is used in many idiomatic expressions where cosa and che cosa do not apply -- notice that in the examples below Che functions as an adjective:
   
   Che tempo fa? How's the weather
   Che ora è? What time is it?
   Che ore sono? What time is it?
   
   
3. Cosa and che cosa are used in some expressions below:
   
   Che cosa non va? What's wrong?
   Cosa non va? What's wrong?
   
   Che cosa c'è? What's the matter?
   Cosa c’è? What's the matter?
   
   in this expression, Che is permitted, although tends to be more informal for use among friends and family: Che c’è? What's the matter?
   
   
4. Che, Che Cosa, and Cosa can be usually used interchangeably when they are all being used as pronouns and not in any of the expressions referenced above:
   
   Che vuoi fare oggi?
   Che cosa vuoi fare oggi?
   Cosa vuoi fare oggi?
   
   What do you want to do today?
   
   
5. Italian, like English, also uses Che, Che cosa, and Cosa in the sense of Che dici or Che hai detto (as in English when we might say "What?" when we've misheard something) when something that has been said seems unbelievable, was not heard or not understood properly.
   
   However, this use is informal (and somewhat rude, even in English). The more appropriate way of saying What? in this context is to ask Prego? (Pardon?) or to ask the speaker politely to please repeat themselves.