Elephant, elephant: Why your nose is so long? Mother said: long Nose is beautiful. I understand this little song in this way.if i am wrong ,please tell me . And about your puzzle, there are some answers ,I hope it can help you . First :才 【cái 】 才+[是]…。含有“别的不是”的意味。如：这才是好样的！this is good ! Cai have many different meanings but when cai with shi it means” the other is not “. In this sentence , “ 鼻子那么长，才是漂亮 “ is means long nose is beautiful . No long nose, no beautiful. (there is not beautiful besides long nose .) Second : 还（还）hái This character has many meanings .for example: 　　⒈仍旧，依然(still)：他身体～健康。He is still healthy. 　⒉更(better)：今年比去年～好。This year is better than last year. 　　⒊再，又(again )：～来一个。Once again. 　　⒋尚可，勉强过得去(ok, so so)：这篇文章～可以。This essay is ok. 　　　5.连词(conjunctions)用于问句(for questions )，〈表〉选择(predicative choose)：是去文化宫，～是去博物馆？Go to cultural center, or go to the museum? and for your question,I think when you say”还是漂亮”,you may want to express “Even though his nose was very long, he was still very beautiful”. “虽然他鼻子很长，但他还是漂亮” It is right .but maybe it is not suitable for the whole meaning of this song. In this song , elephant’s mom want to say :for a elephant, a long nose is beautiful ,besides long nose ,nothing is beautiful.(and I think short nose is not fit for elephant. Do you think so? )

才是在这里没有实际意思，最多起到强调，加重语气。

https://www.youtube.com/watch?v=XktTZPk3Wac 您提示的歌詞 似與我所熟知的有出入 才 : 表示強調的語氣。 如：「我才不幹呢！」、「他哪累著了？我才累呢！」 原作 : 鼻子長是漂亮的 加入 才 表示 強調 這個性質 : 鼻子長才是漂亮的 又例 : 腿短很醜 > 腿長才是漂亮

鼻子那么长，才是漂亮 means if the nose is NOT long, the elephant wont be beautiful. 才 + verb means: if NOT..., we will get an opposite result. for example, 你穿这条裙子好看 means this skirt is good for you.你穿这条裙子才好看 means (only) this skirt is good for you, others are not good. for example, there are three skirts, ur friend asks u which skirt is good for her, u say 你穿这条裙子才好看, which means the two others are not good. if u just say 你穿这条裙子好看, it means this skirt is good but maybe the two others are good too.

elephant, elephant, why is your nose so long, mom says, that long nose makes it beautiful.