Happy New Year everybody,

I was thinking about "I am on it". does it mean that I am going to work on this project or something?
Either "I'll get to work on that" or "I'm already working on that."

I've never heard it without it being contracted: I'm on it!

Happy new year to you as well!
I've heard it without the contraction for emphasis, Barbara. Slight emphasis on the "on."

"You don't have to worry about that. I am on it."
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'I Am On It'?

“I am on it” is an informal, often exclamatory (!) way of saying you are going to do or start something. For example:

Boss: Who wants to take on this project?

Employee: I’m on it!

“I am on it” can also be used to refer to a subject. For instance:

Boss: Who is working on Project A?

Employee: I am on it.

I'm on it. = I'm taking care of it. = I'm handling it. = I'll take care of it right away. = I'll take care of it immediately.

Students: We have free audio pronunciation exercises.
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