A preprocessing step performs macrosubstitution on program text, inclusion of other source files, and conditional compilation.
编译的预处理阶段对程序文本进行宏替换，包含进其他源文件，并进行条件编译。
2
This means that all temporary variables used by a macro are automatically renamed before the substitution occurs in order to prevent them from having conflicting names.
这意味着宏所使用的所有临时变量都会在替换发生之前自动重新进行命名，从而防止名字产生冲突。
3
The money substitution changes people's demand on money, influences a nation's economy and macro policy effect.