Hi Joan,
In a nutshell, the present participle ends in 'ant' but doesn't have an 'en' in front of it.
If it does it becomes a gérondif.
If you take a look at the following Kwiziq lesson you will find more explanation to your answer -
https://french.kwiziq.com/revision/glossary/verbal/le-participe-present-et-le-gerondif
Hope this helps!