PHP bad word replacement comment system - php

Question

I'm trying to create a comment system using php that replaces a commenters bad words with ****. I'm using sql and have a database with two columns, one with the bad word and one with the replacement word (which is the ****). So far, I am able to identify when a user types in a determined bad word and retrieve the replacement word for it, however I am unable to replace that bad word with the replacement word. I tried to do $element = $goodWord after $goodWord = $row['replaceWord'] to say that the new identified bad word should be replaced, however it does nothing. I'm not exactly sure how to set an element within an array in php to a new value. Any suggestions?
code:
if(!empty($_GET["field1_name"])) {
$field1_name = mysqli_real_escape_string($link, $_GET["field1_name"]);
$field1_name_array = explode(" ",$field1_name);
foreach($field1_name_array as $element){
$query = "SELECT replaceWord FROM changeWord WHERE badWord = '$element' ";
$query_link = mysqli_query($link,$query);
if(mysqli_num_rows($query_link)>0){
$row = mysqli_fetch_assoc($query_link);
$goodWord = $row['replaceWord'];
$element = $goodWord
}
}
}

Answer 1

if(!empty($_GET["field1_name"])) {
$field1_name = mysqli_real_escape_string($link, $_GET["field1_name"]);
$field1_name_array = explode(" ",$field1_name);
$newComment = '';
foreach($field1_name_array as $element){
$query = "SELECT replaceWord FROM changeWord WHERE badWord = '$element' ";
$query_link = mysqli_query($link,$query);
if(mysqli_num_rows($query_link)>0){
$row = mysqli_fetch_assoc($query_link);
$goodWord = $row['replaceWord'];
$element = $goodWord
}
$newComment = $newComment." ".$element; // append $element back to back to create modified comment
}
// now update the $newComment back to your comment Table
}