Moodle里的Prevent和Prohibit有什么不同？

For Prohibit, no one will have permission even if you try to set 'allow' on override options.

otherwise if you set 'prevent' (higher context) it will always be defeated by 'allow' (lower context) and vice-versa.

摘自：http://moodle.org/mod/forum/discuss.php?d=63292

这简单的英文应该看得懂吧？