<html>
<head>
</head>
<body>
<input id="inp">
<input id="outp">
<script>
stoplist=[
"и",
"а",
"не"
]
inp.oninput=function(){
outp.value=this.value.split(" ").filter(function(word){return stoplist.indexOf(word) === -1}).join(" ")
}
</script>
</body>
</html>