"I saw the storm approaching."
In above line approaching is describing storm.
Gerund is used as objective complement to describe object.
Participle like an adjective describes a noun or pronoun.
In above line,is approaching acting as gerund or a participle?
Following screenshot depicts support for gerund.
Best Answer
First off, a participle is an inflected form of a verb. In English, there is a present participle, formed by adding "ing" at the end of an infinitive, and a past participle, usually but not always formed by adding "ed" at the end of an infinitive.
Participles are used in three different ways: as part of a compound verb, as an adjective, and as a noun. When a participle is used as a noun, it is called a "gerund." So gerunds are participles used in a particular way.
Second, nouns generally take a possessive pronoun: e.g, "my car" or "her house." In Received English, gerunds follow the general rule and use possessive pronouns. However, this rule is often breached in practice. The source you have cited is describing that when pronouns are tied to a gerund, you may see either an objective or possessive pronoun used. I'd advise using the possessive, but not worry when you fail to do so.
In your example, what do you see? You see a storm. "Approaching" describes the storm: it is approaching rather than stationary or receding. Therefore "approaching" is a participle being used as an adjective.
In your source, "leaving" is the direct object of excuse and so is acting as a noun. When a participle is used as a noun it is called a "gerund."