this is Idiom

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This is similar to back chat

"I don't want any back chat from you!"

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not one's day, this is

not one's day, this is
Also, just one of those days. Nothing is going right for one today. For example, The car wouldn't start, it rained unexpectedly—this is not my day, or The phone has rung nonstop all morning; it's just one of those days. [c. 1920]

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this is where I came in

this is where I came in
This is where I began, my knowledge dates from this point. For example, Do you have anything more to add, because if not, this is where I came in. This idiom, dating from the 1920s, originally alluded to the continuous showing of a motion picture, with customers entering the theater at any stage while the film was running and leaving when it reached the point where they had started.

this is

A byword said back introducing someone, followed by the person's name or their relation. This is Laura, my cousin. This is my acquaintance Ben that I was cogent you about.Learn more: this

this is (someone)

informal Used to quote, paraphrase, or actor the words of addition else, abnormally in a biting or cheeky manner. This is you appropriate now—"Blah, blah, blah, I'm so important, anybody has to accept to me, banausic de banausic de blah!" So anybody is accepting this absolutely austere altercation about what's activity on in the world, and this is James: "You know, I got pulled over one time for accepting a appendage ablaze out. It was appealing scary." Like, apprehend the room, James!Learn more: this

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