The correct way to mix the Chinese characters and Roman alphabets

I wonder what kind of space do we need to put between Chinese characters and Roman alphabets, including formulae? I don’t know how the typesetting algorithm works so I don’t know what is the proper way to do that.

Can you explain better the problem? Note that if you are in math mode and you want to write text then you will have to enter a sub text mode, there the spaces will be treated like usual spaces. In math mode a single hit of “space” key will insert a “function application” not a visual space between glyphs. For real space you need to hit “space tab” for example (if I remember correctly).

This is a question, not a problem, and I was asking general suggestions, which depends on the typesetting algorithm.

Many languages use spaces to break sentences into words. In TeXmacs, the lengths of these spaces are variable determined by typesetting algorithms which also determines where to break lines. (By the way, I know that we can use things like (space "4pt") to fix the length of the space, but of course it should not be generally used.)

However, in languages like Chinese, Japanese and Korean, one does not use spaces to break sentences, so I am not sure what TeXmacs will do when it sees a space in such settings. As a reference, I see that the document made by @sadhen does not use spaces to separate Chinese characters and Roman alphabets or numbers, in particular mathematical formulae. I was simply asking what is suggested.