I'll write what I think of right now. I don't have anything to write.
Yesterday was the third day of Mandarin training. I found it easy to pronounce Mandarin words if I trained my English pronunciation. I see that Japanese language is only special about the way to produce voice. So Maybe other language speaker will less hard to master the pronunciation of other languages than Japanese.
But Japanese has a advantage of studying Mandarin. That's kanji. I can understand what they want to say only through kanji. I realized that when I was young. Japanese is bad at English, but can be good at Mandarin. Great!