An impersonal verb is a verb that exists only in the third person singular. They are said to be impersonal because they do not relate to a person. For example, they are found in verbs used to express the weather: il neige, il pleut...
Il faut que...
il y a...
il s'agit de...
A simple way to see that this is an impersonal verb is to try to replace the "il" with someone's first name. You will soon see that the sentence no longer means anything.
In contrast, we find personal verbs that have a subject that expresses a person or a thing well.
Il est là ==> Jacques est là.
- An impersonal verb is a verb that exists only in the third person singular.
- The subject pronoun "il" means nothing.