Translation:The book is orange, violet, and yellow.
'Flava' is Esperanto for 'yellow'. It just is. And although the style of Esperanto does evolve, very slowly, just like any other living language, 'flava' is not up for discussion. In all languages, some colours are primary concepts, while other colour names are derived from words for something other than a colour, just like the Esperanto for 'pink' happens to be derived from the word for a rose. How about 'rose-coloured spectacles' in English? That's not an irregularity, it's a fact of life. Life is complicated; concepts overlap. 'Golden'? Is that 'Ora'? Or 'Orkolora'? Note the nice distinction you can make in Esperanto. And languages adapt. Some colours get a word of their own. Other colours are an afterthought and share a root with a flower or something else. That's not a problem. It's how all languages have to work, otherwise they'd be frozen in stone and everybody would be tongue-tied :-) Where Esperanto scores is that there are fewer rules to learn.
Purple, orange, and pink got their names from things in several languages, and are treated differently in those languages.
For example, in Spanish, to refer to a pink book you say, "libro rosa" even though libro is masculine. A red book, on the other hand, would follow the general rules of matching gender, ie "libro rojo" but "camisa roja."
I've encountered this in a few languages now, so it makes sense to me that Esperanto would preserve the color-of-something concept for such colors.
Violo = ”Viola”-” a genus of flowering plants in the violet family Violaceae” [en.wikipedia] :) http://sklep.myflowers.pl/images/A1_Foldery/10_BUKIETY/Z66/DSC_7406_1.jpg
It seems unfair when i get this wrong when I miss hear the guys pronunciation of the sentences, some words sound together when they are the same, its as if im being marked solely on his tone and speed when in reality there is so many other tones and speeds that speak Esperanto, maybe adding a slowing down button