Explain the concept of verbal nouns and their usage.

Verbal nouns, also known as gerunds, are nouns derived from verbs. They are formed by adding the suffix "-ing" to the base form of a verb. Verbal nouns function as nouns in a sentence, but they retain some characteristics of verbs.

The usage of verbal nouns can be categorized into three main functions: subject, object, and complement.

1. Subject: Verbal nouns can be used as the subject of a sentence. For example:
- "Swimming is my favorite hobby." (Here, "swimming" is the subject of the sentence.)

2. Object: Verbal nouns can also function as the object of a verb or a preposition. For example:
- "I enjoy swimming." (Here, "swimming" is the object of the verb "enjoy.")
- "She is interested in painting." (Here, "painting" is the object of the preposition "in.")

3. Complement: Verbal nouns can act as a complement to a linking verb, providing additional information about the subject. For example:
- "Her passion is dancing." (Here, "dancing" is the complement of the linking verb "is.")

Verbal nouns can also be modified by adjectives or other nouns, just like regular nouns. They can be pluralized and possessive forms can be used as well. Additionally, they can be used in compound nouns, such as "swimming pool" or "running shoes."

It is important to note that verbal nouns should not be confused with present participles, which also end in "-ing." Present participles are used as verb forms, while verbal nouns function as nouns.

In summary, verbal nouns are nouns derived from verbs by adding the suffix "-ing." They can be used as subjects, objects, or complements in a sentence, and they retain some characteristics of verbs.