Simplify the following text for a Grade 10 native English-speaking person.
Original: Unlike the case for Euclidean polytopes , an abstract polytope with regular facets and vertex figures may or may not be regular itself -- for example , the square pyramid , all of whose facets and vertex figures are regular abstract polygons .
Simplified: Regular polytopes have regular facets ( faces to speak from the 3D viewpoint ) , and their vertex figures are regular .