I create a form and I want to use PHP to remove **all HTML tags** but **exclude some tags `(<b>, <strong>, <em>, <i>, <p>, <br>, <ul>, <li> <ol>`... (and some tags for format paragraph)** when members click Submit befor it will be insert into Database.

```
$content = $_POST['content'];

```

Thanks all for help.  

I'm sorry if my english isn't good.