The Cut command deletes the selected entities. When database or grid entities are cut, their parent and child entities are deleted as well. The selected entities and any parent entities associated with them replace the current contents of the paste buffer. For example, if a trimmed surface were selected and cut, the untrimmed surface and trimming curves it was based upon would be cut as well. All of these entities would be placed in the paste buffer.
Tip: To physically separate linked entities and perform a transformation on them, you must Cut the entities first and then Paste them with your desired transformation.