How can I do a Random phrase generator using the txt file reader in Java without array

I must create a Java program that reads a .txt file and output a random phrase that the same read.

String line1,line2,line3,line4,line5,line6,line7;

    int n;
    Random rd = new Random();
    try{

        BufferedReader br = new BufferedReader(new FileReader("Phrases.txt"));
        while(br.ready()){
            line1 = br.readLine();
            line2 = br.readLine();
            line3 = br.readLine();
            line4 = br.readLine();
            line5 = br.readLine();
            line6 = br.readLine();
            line7 = br.readLine();
            n = rd.nextInt(7);
            String lines=line1+line2+line3+line4+line+line+line7;

            for(int i=n;i<n;i++) {
                System.out.println(lines);
            }
        }
        br.close();
    }catch(IOException ioe){
        ioe.printStackTrace();
    }

If I try to output any of the variables "line", it will print the phrase corresponding from the txt file.