To understand the concept of finite verbs , it might be helpful to first look at the concept of tenses. 
Tenses are an indicator of time. A change in time leads to a change in the tense of a verb.
Why is there a need for tenses ?
The following logic could help you understand the need for tenses :
- Verbs are actions ; actions are based on time ; time is indicated by tenses : Hence verbs have tenses . Verbs which fall under this category are known as Finite verbs
- Similarly verbs which are actions and are not dependent on time will not take tenses.Such verbs are known as non-finite verbs
The below image will help you understand these things a bit better :
Due to this reason the concept of tenses is applicable only for the finite verbs.
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