是primar-level还是primary-level?

是primar-level还是primary-level? fine schooling, be it primar-level, secondary-level or terti fine schooling,be it primar-level,secondary-level or tertiar LEVEL be it primary-level的用法 at level 还是 on level 牛津高阶上用的的是on a level 表示在同一水平上, level的介词词组有哪一些比如 at .level之类的,在什么程度是用at level还是on level? above the sea level 还是above sea level? high-level level e level吗 level road?