The word porridge doesn't seem to be used much in English, at least in the US. I think in England (and perhaps in Jamaica because of British influence) they refer to oatmeal as porridge. I wish they would just define Kasha as "hot cereal" to clear up confusion.
When is the 'y' used to substitute an end letter in a Ukrainian noun, please? I cannot seem to find the rule.
Cereal ought to be accepted. At the very least, oatmeal given we're talking about American English here...
Porridge is an English world. Not everyone on this site is American. Please don't try and ruin our language more than you already have.
Ruin whose language? And who is going to ruin it?
This is not an English course but a Ukrainian one. Different alternatives could easily be accepted, anyhow. Besides, from context I think he just meant American English is used in the course, not that it is solely mandated.