A present participle is a verbal that is used as an adjective or for verb tense. It is one of two types of participles, along with past participles. The present participle of most verbs has the form base+ing. For example, the present participle of the verb "laugh" is "laughing". Present participles can be used in many different ways, including:

• Continuous form of a verb: The present participle is used to form the continuous form of a verb. For example, "I am laughing" uses the present participle "laughing" to indicate that the action is ongoing.

• Adjective: Present participles can be used as adjectives to modify a noun or pronoun. For example, "the laughing gnome" uses the present participle "laughing" to describe the gnome.

• Two actions at the same time: When two actions occur at the same time, and are done by the same person or thing, we can use a present participle to describe one of them. For example, "whistling to himself, he walked down the road" uses the present participle "whistling" to describe the first action.

It is important to note that present participles should not be confused with gerunds, which are nouns formed from verbs. Gerunds also end in "-ing", but they function only as nouns.