And because "A can speak Japanese, D can't speak Japanese, and B can't speak English; Explain that all three people can only speak "French or Chinese"; Then there is "no one can speak Japanese and French at the same time", so this language can't be "French", only "Chinese".
In the end, "① A, B and C can speak two languages each, while D can only speak one language;
So there are: Japanese and China.
Ding-China people
C- English French 4A and C, C and D can't talk directly.
B- Chinese, French, B and C can talk directly, and B can't speak English.