Original sentence: " They are a subset of the plugs on a car engine cylinder block or cylinder head.Core plugs are found on engines and are used to plug the holes where sand cores have been held.Freeze plug is another name for core plug or expansion plug, and is commonly referred to as a "frost plug.They are often wrongly called Freeze plugs
Edited sentence: Core plugs, sometimes wrongly called freeze plugs or frost plugs, are found on engines and are used to plug the holes where sand cores have been held.They are a subset of the plugs on a car engine cylinder block or cylinder head