var elem = document.createElement("p");
var txt = document.createTextNode("My dog has fleas.");
elem.appendChild(txt);
document.body.appendChild(elem);
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var myEm, myP, txt1, txt2;
myEm = document.createElement("em");
txt1 = document.createTextNode("very");
myEm .appendChild(txt1);
myP = document.createElement("p");
txt1 = document.createTextNode("I am ");
txt2 = document.createTextNode(" happy to see you.");
myP.appendChild(txt1);
myP.appendChild(myEm);
myP.appendChild(txt2);
document.body.appendChild(myP);