What does "I'm all talk." mean?

Question

What does   "I'm all talk."   mean?

Answer

Hi,  the full sentence is " I am all talk and no action"
It refers to people who say they are going to do something but never do it. 
Example: 
That guy is all talk and no action.  For  5 years, he's  been saying that  he's going to improve our work conditions  and nothing's happened so far.

Answer

talks about doing big, important things, but doesn't take any action.

other similar idiom
He is all talk and no trousers

http://www.usingenglish.com/reference/idioms/all+talk+and+no+trousers.html

Answer

Another phrase that means the same thing but is probably more self explanatory is "He is all bark and no bite."  Imagine a dog that barks but doesn't bite.

Answer

all talk, no action

Answer

it's means that only talk and not to act

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