This
The word “this” is the other one from that. You
use this to refer to a person or thing that is near
you now, to the place where you are now, or to
the present time. When there are two or more
people or things near you, “this” refers to the
nearest one.
For example, THIS person whom we both know,
aside from us who eyed each other: something
or someone between us, that other person who
is nearer to touch, who hooked us up for a blind date.
A
The word “a” or “an” refers to someone or
something for the first time and your listener
or reader may not know which particular thing
you mean. It is to emphasize singularity: just and
can be any one or any thing, not exactly that one.
Not quite this.
For example: you were just A person, A dream,
until you became THE person, mine.
