I have tried many different ways ... see commented out code
public static void main(String[] args) {

    a = "Hello, ";
    b = "Amigo!";

    printString("Hello, Amigo!");
        // printString(s);
        // printString(a + b);
    }

 public static void printString(String s)
    // System.out.println (s);

    // a = "Hello, ";
    // b = "Amigo!";

    // nope  System.out.println(s);
    // nope  System.out.println s;
}