can someone help me

Instead of being irate about it and blaming others for not spoon-feeding you information, you should have found out yourself and look up sources etc.Most Practioners , be it newcomers or those experienced to the respective different topics of arcane studies are supposed and usually expected to know what is stated in the next paragraph.

As for what is impossible, it can be simply stated as one that defies the laws of a particular plane as long as that particular form,manifestation or body is subjecticated to it.

That is all ^_^

Fluffs are members that talk complete nonsense and are very ignorant people.