1. Che cosa / Cosa / Che --- are used in the same way. They refer to a non-Person that is the Subject of an action, or to a Direct object. eg * inanimate Subject @ What went on? = Che è successo? = Cosa è stato? = Che cosa è successo? * direct object @ What did you buy for lunch? = Che cosa hai comprato per cena = Cosa hai comprato per cena? = Che hai comprato per cena? 2. You can see "Che cosa" as "Quale cosa", but "Quale" implies a choice among many or a set of many things anyway, so -- besides the distinction is a bit fluid -- we use it in a specific way, anyway: *choice among things @ Which one is the best for you? = Qual è il migliore per te? (= Quale cosa //Which thing// è la migliore per te?) *set of things @ What consequences because of that fact? = Quali conseguenze ha avuto quel fatto? Note - Consider that in "Qual è" we don't use the apostrophe for dropping the last letter. I learnt it last week but I still write it, so my actual version of Qual*è is with the deleted apostrophe. [EDIT - added few more examples. An "inanimate Subject" is a bit of contradiction so we tend to change the structure as for "consequences caused by natural events" so we tend to use "Quale": @Which dog bit you ? = Quale cane ti ha morsa(♀)?

Hi! First is Cuándo (When). Che it's like Hey! For example:¿Che me podes escuchar? (Hey! Can you hear me?). Cosa it's like thing. For example:¿Me pasas esa cosa? (Can you give me that thing?).But I don't know what means "quale" sorry. I hope it's useful for you! If you want we can talk.

Grazie!

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