var first = 'ma';
	var second = 'il';
	var third = 'to:';
	var address = 'webmaster';
	var domain = 'physics.harvard';
	var ext = 'edu'; 
	document.write('<a href="');
	document.write(first+second+third);
	document.write(address);
	document.write('&#64;');
	document.write(domain);
	document.write('.');
	document.write(ext);  
	document.write('">'); 
	document.write('<em>send email</em></a>');