继续翻译

* A "directive" is an instruction for `make' to do something special      while reading the makefile.  These include:                                                        * Reading another makefile (*note Including Other Makefiles:           Include.).                                                        * Deciding (based on the values of variables) whether to use or           ignore a part of the makefile (*note Conditional Parts of            Makefiles: Conditionals.).                                                        * Defining a variable from a verbatim string containing           multiple lines (*note Defining Multi-Line Variables:           Multi-Line.).

指令就是一系列需要 make 在读取 makefile的时候要做的事情。包括：

   读取另一个 makefile (*note Including Other Makefiles: Include)

   决定(根据变量的值)是忽略还是使用 makfile的某一个部分

   (*note Conditional Parts of Makfiles: Confitionals.)

   * 从一个多行字符串来定义一个变量(*note Defining Multi-Line Variables: Multi-Line.)

后文待续