Wait so kawaii desu=to be cute? interesting
"
Desu" is a positive copula, it's hard to explain unless you've heard it used before, but basically it marks a statement as true. For example:
"Kore kawaii desu""
Kore" = this, "
kawaii" = is cute, and "
desu" is the positive copula, what this statement means is "That is cute.".
"Kore kawaikunai ja nai""
Kore" = this, "
kawaikunai" = not cute, and "
ja nai" is the negative copula, what this statement means is "That is not cute.". In Japanese positive copulas follow positive statements, and negative copulas follow negative statements.
It's also a sentence ending you use in Japanese in order to be polite. However, for things like "kawaii desu", it would be "to be".
I think.
Well polite in the sense of not being lazy in most cases. "
ringo taberu desu" isn't that much more polite than "
ringo taberu", and not near as polite as "
ringo tabemasu". You may be thinking of the way you can sometimes omit the particle "
ni" in lieu of the positive copula "
desu" which only makes it sound more polite because it goes back to that being lazy part.
まほ~