>There is written
It's written...
>I'd like to ask
>about this expression, what does mean, is should be only a declaration
>or it should be some formal statement of my income?
Jeśli nie radzisz sobie z długimi zdaniami, podziel je na kilka krótszych.
>I looking forward to hearing from you.
Jeśli już to "I AM looking..." ale w formalnych listach pisze się "I look forward..."