请大侠分别解释一下A Level, AS Level & GCSE.申英,请大侠分别解释一下：A Level, AS Level & GCSE.还有A*Grade

请大侠分别解释一下A Level, AS Level & GCSE.申英,请大侠分别解释一下：A Level, AS Level & GCSE.还有A*Grade a-level 预备级 英语怎么写来着?是AS-LEVEL 还是 PRE A-LEVEL 来着的 忘记了 GCE'N' Levels是什么标准,O'level ,A'level 有是什么标准?GCE N'level,O'level,A'level 分别是什么标准,如何达到这些标准.》 on a less sensational yet just as powerful level. 请各位大侠解释一下 增烨的意思.谢谢 A level as is shown in ?as is shown in请解释一下 请各位大侠解释一下下面这张星图是啥米东西?上面的几颗星分别是什么?代表啥米意思.敬请点评. ?classified as a master because of its advanced level,the course, classified as a master because of its advanced level, teaches knitting technique and design font-size:100%是什么意思?A headingA paragraph这段代码我似乎有点看不懂.请大侠帮忙.解释一下.font-size:100%与font-size:20px的关系 有没有as+形容词+as if的表达?如,He was excited as if watching a world-level football game. ___ writing stories,Mr.Green loves reading and listening to music. A. As well as B.In addition to请详细解释一下两个选项的区别 请解释一下最小二次回归有哪位大侠可以解释一下什么是最小二次回归（least squares regression)? I am a trill seeker and like to always take it to that next level as as a high-level test 作为高水平的测试,对吗?谢谢 A-level和O-level是什么? 关于电磁场与电磁波的问题平均波印廷矢量有什么意义吗?请大侠解释一下 请各位大侠帮忙解释一下什么是“nei’s基因多样性?”该怎样读啊?谢谢!