Our earthly space is three-dimensional. Language grammar belongs with the estimable heights, widths, and depths or lengths, along with the human need for fresh water, air, good clothing, and a decent roof. Grammar is a basic human need. It is healthy to have a good business with grammar.
 
Language has much reference to time. When we talk about a thing or a person, we usually think if something or someone — is, was, or will be. This means we need grammar for the Present, Past, or Future.
 
However, we cannot touch time. We cannot see or hear time. Clocks can show values only as we set them, and grammatical time is not the same thing as the hour.
 

 
How can we learn the grammatical time, then? To an extent, we may think about time together with place. 
 
We can reason on the human experience we know as language use. The way we people use language can show a bit of that human and intellectual skill to manage own speech faculty.
 
How can we use a word as “before?” Could we say “before that turn”, for a place, and “before ten”, for a time?
 

 
“Before the turn” says “before the place”.
“Before ten” says “before the time”.
 
We can use the word before to speak about time, as well as place. In all natural languages, human minds have a flexible habit to connect time and place. Humans have evolved grammars along with perception for three-dimensional space.
 
Let us elaborate on this fact for grammar.
 
We can think about three places, and name them TODAY, YESTERDAY, and TOMORROW.
 
Could there be a town named Tomorrow?
 

 
This could be our Tomorrow town.
 

 
Could there be an estate named “Yesterday”?
 

 
Well, this could be a good idea for our Yesterday.
(Bodie is a ghost town in a history park in California, USA.)
Such place names would be unusual, but possible.
 
Let us envision fields we name the PAST, PRESENT, and FUTURE. They can be our Fields of Time. To learn the grammatical time, we learn to manage our Fields of Time.
 
In grammar as well as in day-to-day living, our views depend on our knowledge. We could say that our knowledge is the light we have. Let us think about Fields of Time and sunlight.
 
Knowledge needs memory. PAST things happen to go into oblivion, as the learning matter we do not review or work with.
 
For our PAST field, we can envision the light as with a setting sun: there is shine enough, if we want to return to the matter.

 
We do not have memories of the FUTURE, but we can plan our learning. For our FUTURE field, the shine can be as with sunrise.

 
It is our PRESENT we have the most potential to shape. In our PRESENT field, the sun is high and daylight broad.

 
Let us picture a word that matters a lot in grammar and life, the verb to be, in the Field we name the PRESENT.

 
Let us envision the verb to be in the other Fields of Time.
 

 
This is how the verb to be can look in all our Fields.
 

 
We can feature two other important words, to have and to do, in our Fields.
 

 
This is how the verb to have alone could look in our Fields of Time.
 

 
This is how the verb to do could look in the Fields of Time.
 

 

 
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What do we do, to feature words in our Fields of Time? We put together our thought about the grammatical time and person.
 
For a start, we can think about s as the feature for the pronouns he, she, and it.
 

 
Pronouns are words that can stand for grammatical persons. The words I, you, we, they, he, she, and it, are personal pronouns.
 
The persons are “grammatical”, as they can stand for human beings, or things, events, or other objects of thought. They also can refer to fictional characters or objects, and people in stories do not have to be real, either.
 

 
We can say that he is someone, he has something, or he does something. Similarly, we can say that she is someone, she has something, or she does something.
 

 
The feature “s” holds only for the singular, that is, single persons, creatures, things, events, or phenomena — in short, objects of thought — in the grammatical PRESENT.

 
How important are our three words, be, have, and do? They can be our core grammar words. We can use them cognitively to map the grammatical time in language.
 
When fashioning words with features becomes our habit and nature, we get more real time to think what we want to say. We do not need very much time to think how to speak or write. Feel welcome to try 1.1. THE FIELDS OF TIME, BASIC PRACTICE.

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