Mooncakes is yue bing or 月 饼. In English it can be pronounced ye bing.
Moon cake started when if we can.
Not a french word that I know. If you mean a small cake, eaten at breakfast, shaped like a crescent moon, then it is a croissant.
凯尔塞 the Chinese pronunciation is something like this: Kǎi ěr sāi
In Chinese, the word "hello" is spelled 你好 (nǐ hǎo).
Kuchen
A piece of cake is simply called (and spelled) "a piece of cake." It may also be called "a serving of cake" or "a slice of cake."
spell piece
Cake in spanish is "biscocho" pernounced: bees-coh-cho
Chinease is not a language therefore you can not translate
The dessert, or the verb (to encrust or to collect in lumps) is spelled "cake".
une génoise
The spelling Kuchen is German for "cake."