1.up to the present, the existence of exogamous "tribes" has not been demonstrated anywhere.
外婚制“部落”的存在,直到现在也没有在任何地方找到证明。
2.He did not by any means discover the existence of exogamous groups; still less did he understand them.
他根本没有发现外婚制集团存在的事实,也完全没有理解这个事实。