propsyntaxpanel.setBorder(BorderFactory.createTitledBorder("Propositional syntax"));
        propsyntaxpanel.setLayout(new BoxLayout(propsyntaxpanel, BoxLayout.PAGE_AXIS));
        modalsyntaxpanel.setBorder(BorderFactory.createTitledBorder("Modal syntax"));
        
        mainframe.getContentPane().setLayout(new BoxLayout(mainframe.getContentPane(), BoxLayout.PAGE_AXIS));
        //JTextArea gendesc = new JTextArea("Molle supports parenthetized formula expressions with propositional and modal operators.");
                //gendesc.setLineWrap(true);
        //gendesc.setPreferredSize(new Dimension(300,200));
        mainpanel.add(new JLabel("<html><h1>Formula syntax</h1> <p>Molle supports <i>parenthetized</i> formula<br>expressions with propositional and<br>modal operators.</p> <p>A formula is a composition of subformulas<br>with propositional or modal operators.</p> <p>Such operators are recognized as follows:</p> </html>"));    
        
        propsyntaxpanel.add(new JLabel("~     NOT"));
        propsyntaxpanel.add(new JLabel("&     AND"));
        propsyntaxpanel.add(new JLabel("|     OR"));
        
        modalsyntaxpanel.add(new JLabel("[]   NECESSARILY"));
        modalsyntaxpanel.add(new JLabel("<>   POSSIBLY"));
                        mainframe.getContentPane().add(mainpanel);
        mainframe.getContentPane().add(propsyntaxpanel);
        mainframe.getContentPane().add(modalsyntaxpanel);
        
        mainframe.setResizable(false);
        mainframe.pack();
        mainframe.setVisible(true);