1. By Marsha Barrow

2. A gerund is: a verbal (a verb form used as another part of speech).
a verb form ending in -ing used as a noun.  It can be in the position of subject, direct object, object of the preposition, or predicate noun.

3. Examples: Subject - Reading is my favorite activity.
Direct Object - I enjoy reading.
Object of the Preposition - Rainy days are good days for reading.
Predicate Noun - My favorite subject is reading.

4. The subject of a sentence is the person, place, thing, or idea that is doing or being something.
A direct object follows an action verb, and answers the questions who or what. The direct object receives the action from the subject. It must follow an action verb, not a verb “to be” (am, is, are, was, were, be, become, became).

5. Prepositions are words which begin prepositional phrases such as for, on, in, by, about, to, etc. The object of the preposition is the noun that follows a preposition.
A predicate noun follows a form of the verb “to be.” A predicate noun renames the subject of a sentence.

6. Remember this: Do these steps:
A word ending in -ing can be either a verb, a participle or a gerund.  To determine which one it is, you must determine how it is used in the sentence.
Do these steps:
 Find the simple subject and simple predicate (verb).
 If the -ing form of the verb is not part of the simple predicate (verb), then determine how it is used in the sentence.  Is it in a noun position?  Then it is a gerund.  If it is used as an adjective, then it will be a participle.

7. Examples:
Bill and Tony are running.           are running is the verb in this sentence.
Bill and Tony enjoy running.           running is a gerund, a direct object of the action verb, enjoy.
The running water overflowed.           running is a present participle (adjective) modifying the noun, water.