object cant inherit properties - object

Question

I get stack. PLZ help.
In class "work" i creating a frame of a table. Than in object "myWork1" i must fill that frame of a table.
But it didnt works. Finally i want to creating a table with special information in it.
What im doing wrong?
<p id="demo">demo</p>
function work(td1) {
this.firstWork = function(){
var table = document.createElement("table");
var table_tr = document.createElement("tr");
var table_td = document.createElement("td");
var table_td_text = document.createTextNode(this.td1=td1);
table_td.appendChild(table_td_text);
table_tr.appendChild(table_td);
table.appendChild(table_tr);
io.appendChild(table);
}
}
var myWork1 = new work("111");
document.getElementById("demo").innerHTML =
return myWork1.tableWork();

Answer 1

<p id="demo">demo</p>
function work(td1) {
this.firstWork = function(){
var table = document.createElement("table");
var table_tr = document.createElement("tr");
var table_td = document.createElement("td");
var table_td_text = document.createTextNode(td1);
table_td.appendChild(table_td_text);
table_tr.appendChild(table_td);
table.appendChild(table_tr);
return table;
}
}
var myWork1 = new work("111");
document.getElementById("demo").appendChild(myWork1.firstWork());
A working example here : jsfiddle