Parameters can be passed to a SUB or a FUNCTION either by reference or by value. Unless otherwise specified, a parameter is always passed by reference. That means that a SUB or a FUNCTION gets the parameter and can read and modify its value.
可以通过引用或值将参数传送到子程序或函数。除非特别指定，通常是通过引用传送参数。这意味着子程序或函数可以获取该参数，并且可用读取和修改参数值。