Help me to improve speaking in English

English as a Second Language Listening, speaking, pronunciation and accent
21

Dear all,

which of these sentence below is correct?

This is to inform you that your salary has been increased by 12% from February, 2010.
Or
We are please to inform you that your salary has been increased by 12% from February, 2010.
Or
This is to inform you that there is increment in your salary by 12% from February, 2010.

22

I think the right way is " This is to inform you that there is increment in your salary by 12% from February.