Request for more information
A common letter will be a request for more information.
If the application is still under consideration, it will come from UDSKiOR.
If the application has been approved, it will come from ZUS.
You can find some common translations in this letter here.
An approval letter can be recognized by the fact that it will be accompanied by many other papers.
But another indication is the Polish word “przyznaję” in bold under the applicant’s name. “Przyznaję” has the meaning of “I award“, “awards” or “awarding“.
You can find a sample letter here, and you can see a breakdown of the letter’s structure here.
A denial letter is recognized by the Polish word “odmawiam” under the name of the applicant. “Odmowiam” means “I refuse“.
You can get a better understanding of the structure of the letter, and where to find the reason for the refusal, here.