This recent question brought to mind a question of my own. The Japanese name for the Twenty-One Demands made by Japan in 1915 to the Republic of China is romanised on the wikipedia page as 対華二十一ヵ条要求 ...
I just received an email ending like this: 是非是非また誘って How to read the ? Zero results on Google. As for the meaning, is it equivalent to よ ?