// HelloWorld2.java - simple variable declarations
class HelloWorld2 {
    public static void main (String[] args) {
        String word1;   // declare a String variable 
        String word2, sentence;  // declare two more 

        word1 = "Hello, ";
        word2 = "world!";
        sentence = word1.concat(word2);
        System.out.println(sentence);
    }
}