regex to replace a given word with space at either side or not at all

Question

I am working with some code in PHP that grabs the referrer data from a search engine, giving me the query that the user entered.

I would then like to remove certain stop

Answer 1

You can use word boundaries for this

$keywords = preg_replace('/\bfor\b/', '', $keywords);

or with multiple words

$keywords = preg_replace('/\b(?:for|sale)\b/', '', $keywords);