var user = document.getElementsByTagName("li")[0];
var pos = 0, span = user.getElementsByTagName("span")[0];
var pos = 0, span = user.getElementsByTagName("span")[0];
var phrases = [
{name: "city", prefix: "I am from "},
{name: "food", prefix: "I like to eat "},
{name: "lang", prefix: "I like to program in "}
];
user.addEventListener( "click", function(){
var phrase = phrases[ pos++ ];
// Use the .dataset property
span.innerHTML = phrase.prefix + user.dataset[ phrase.name ];
}, false);
span.innerHTML = phrase.prefix +
user.getAttribute("data-" + phrase.name );
user.getAttribute("data-" + phrase.name );