[verb participle] + شودن Construction
I've been seeing sentences containing a participle of a verb and then a form of the verb شودن. For instance:معمولا نوشته نمی‌شوند.نباید حرکتی نوشته شود.جور دیگری خواننده می‌شوند.The problem is, I don't know how or when to use this construction. I would be very grateful if I could be provided with explanation for this along with some example sentences.Thank you very much in advance for any help!

Question

Answer

we use this construction when it is not important for us who did sth or simply we don't know, so the subject doesn't appear in the sentence.
for example:
او نامه می نویسد. (she/he writes a letter)
 نامه نوشته می شود. ( the  letter is being written)
you can learn more by searching for (جملات/افعال مجهول).