Which part?
All Japanese people learn English at school; few learn Chinese as you can verify by reading about the Japanese school system from various sources including Wikipedia.
Similarly in China, English is the only mandatory foreign language taught at school.
Frequently, Chinese or Japanese. For example companies in these countries employ translators. Are you suggesting they rely on primary school-level English to negotiate?
[0] https://en.wikipedia.org/wiki/English-language_education_in_...
> The following is the set of compulsory subjects currently taught in the Japanese education system from the primary to secondary levels:
> * Foreign languages: English (rarely: Korean, Spanish, Arabic, French, German, or Chinese)
That is to say, I would not be surprised if, in China, people are quiet fluent in English.