5 - years ago vs years back

[FirstScript]

Sentence 1 - I met him three years ago.
Sentence 2 - I met him three years back.

I get the feeling "years back" is not really correct except in certain contexts, but I am not sure. I know "years ago" is correct. But how is "years back" wrong?



Help please?

[Horsa]

It's ok but colloquial and usually only in speech.

[apex2000]

Sentence 1 - I met him three years ago.
Sentence 2 - I met him three years back.

I get the feeling "years back" is not really correct except in certain contexts, but I am not sure. I know "years ago" is correct. But how is "years back" wrong?



Help please?

Your feeling is right - we would never say 'years back'. You may hear it in some dialects but it is not good English. For the same reason we would not say 'years forward'. I will meet him in 3 years time.
Back and forward refer to movements. You can say 'I want to go back in time', 'I want to go forward in time'.