what do you mean by "对呢” , well.. if you want to ask if the sentence is authentic, we use "对不对“ or "对么”or “对吗”, they all mean "is it correct?".
The sentences you've written has a small mistake, we don't say" 他 就是 那倾国倾城的容貌 ” ( X he is a very good appearance) we say "他 有 那倾国倾城的容貌“ ( he has a very good appearance) 倾国倾城 adj means very beautiful. Usually "倾国倾城” is used to modify a FEMALE, so we don't say "他 有 那倾国倾城的容貌“ ( he has a very good appearance) often, but "她 有 那倾国倾城的容貌“ ( she has a very good appearance)