You can create composite fonts using any one Roman font and the Simplified Chinese Song-Medium-H font. For example, the following PostScript code defines a composite font, Times-Italic+Song-Medium, which uses Times-Italic for ASCII characters and Song-Medium horizontal font for Simplified Chinese characters:
/Times-Italic+Song-Medium
13 dict begin
/FontName 1 index def
/FMapType 4 def
/Encoding [ 0 1 ] def
/WMode 0 def
/FontType 0 def
/FontMatrix [1.0 0.0 0.0 1.0 0.0 0.0] def
/FDepVector [
/Times-Italic findfont
/Song-Medium-H findfont
] def
currentdict
end
definefont pop