Non finite vs Finite verbs: The Difference

Non-finite Verbs and Finite verbs are the major classifications of verbs compared to other classifications such as transitivity, linking verbs, stative verbs, etc. This is because every other classification stems from both of them though finite verbs take a higher percentage.

Non finite verbs

Non finite verbs are verb forms that lack grammatical properties of inflection. That is, this category of verbs do not get conjugated to reflect: person, number or tense.

For example;

1. He gone to school when you arrived.

The main verb, 'gone', in the sentence is a non-finite verb because it fails to provide information about the number of the subject—whether plural or singular, the point of view of the subject—whether first, second or third person, and finally it failed to give adequate information about the timing of the action (present or past). Note that, even though the verb 'gone' may seem or appear like a past tense verb, it is infact a past participle while 'went' is the past tense of 'go'. The reason why the past participle 'gone' is regarded as a non-finite and not a finite verb even though it is in past form is because past participles have a structural formula of occurrence. 

The structural formula is: had + (-en), for example: had broken, had seen, had known, etc. 

So for every instance where you have a past participle verb functioning as the main verb of a construction, it must be preceded by the primary auxiliary verb 'to have'. 

Another reason why the verb 'gone' is considered a non-finite verb is its heavy dependence on circumstantial information. For example, you cannot say: 'He had gone home' and end the statement like that, it would be incomplete in meaning hence the need to attach circumstantial information to it. For instance: 'He had eaten when I saw him.' Past participle verbs are actions that started at a time in the past and ended in the past but still rely on the verb 'to have' for inflectional functions and on circumstantial information to be meaningful.

Another example is:

He going to the store. 

There is nothing about the verb 'going' that gives us information about the person, number or tense of the subject 'he' and so automatically it is a non-finite verb. The correct representation is:

He is going to the store. 

Present participles are basically verbs that indicate ongoing actions but fail to account for basic inflectional requirements of a sentence or clause.

Other non-finite verbs are gerunds, infinitives, and base form verbs. For example;

1. Singing is my hobby. (Singing here is a gerund)

2. To ere is man. (,To ere is an infinitive)

3. You can be happy. (be is a base form verb.)

Finite verbs

Contrary to what obtains in non-finite verbs, finite verbs are verbs that possess grammatical properties of inflection. They can be conjugated to reflect tense, number, and person in structures. Finite verbs ensure the grammaticality of constructions by exhibiting the relationship that exists between subject and the verb—subject verb agreement. For example;

1. He is a boy.

2. She can dance

3. It is went well.

4. They laughed hard.

5. It is happening now.

Main Verbs or lexical verbs can be finite when they are the only verbs present in constructions, e.g

1. She dances well

2. He cooked fast

Primary Auxiliary Verbs are always finite unless they are used in their base form. For example;

1. He has good taste.

2. It is well.

3. She did a good job.

Modal Auxiliary Verbs are a category of finite verbs that do not reflect person, number or tense (in some cases), but they signify the fourth aspect of inflection which is mood. For example;

1. She can drive.

2. It will work today.

So the differences between non-finite verbs and finite verbs is that non-finite verbs lack inflectional properties to reflect person, number or tense while finite verbs possess those qualities.