Verbs

Verbs are often understood to be the action in a sentence. However, they also express a sense as in the perception of another person or a mental state of someone. They may also serve as a connecting function.

Examples:

Lora feels inspired

Lani seems contented

Jim expects a package in the mail.

Steve is the youngest member of the club.

The derivation suffixes can also help with defining a verb, the suffixes added to a root to make the root a verb are: -ize, -ale, and ify.

Nation: Nationalize

Motive: Motivate

Solid: Solidify

The Infinitive of a verb: appear with the word "to" in front of it. 

Example: "to walk"

We are going to walk to the store.

Bare Infinitive or Base form: commonly used as a helping verb, used without "to"

Example: Leave

He can't leave yet.

Present participle: Formed by adding the suffix "ing"

Laughing

Studying

Past Participle: The word that occurs in the blank space after "have" or "had"

Talked

Eaten

Verbs that Identify with a particular time

Present Tense: Used in third-person-singular and typically have a suffix of "-s" or "-es" if the subject is a single noun phrase or the pronouns; He, she, or it.

Past Tense: Typically has the suffix -ed attached to the base form of a root. It can be used for all subjects and isn't restricted like the present tense.

The complicated part is determining what is Past Participle and what is a Past tense. Some examples would be:

To laugh

Base form: Laugh

Past Participle: Laughed (I have never laughed so much)

Past Present: Laughed ( I laughed all day yesterday).

In the Past participle the verb follows "have" which fits in the description for past participle. In the Past present you know exactly when the laughing happened so since it identifies with a particular time, it would be the finite past tense, and not nonfinite.

Below is a link to a Microsoft word document with a table of the Past Participle and Past Present verb conjugations.