As to 与 As for 用法小结
在英语中表示“就……而论”“有关”或“至于”含义的词语颇多，其中 as to 和 as for 亦表此义，但二者用法不尽相同。
as to 的功能类似于 with regard to， regarding， on the matter of， concerning 等，常用于相当正式的语境中，尤其用于争论和做出决定时。可放于句首或与 wh- 疑问词引导的动词不定式和名词性从句连用（有时可省略），而 as for 无此种用法。例如：
As to the journey， we must decide about that later.
至于旅行，我们必须以后再作决定。
As to the flood， I have heard nothing.
至于那次水灾，我没听到什么。
Nobody could decide （ as to ） what to do.
谁也不能决定该做些什么。
He is very uncertain as to whether it's the right job for him.
关于他究竟是否适合做这项工作，他实在拿不准。
A question arose as to who should be the monitor.
关于谁当班长的问题出现了矛盾。
I want to find out as to whom this bicycle belongs to.
我要打听出来这辆自行车是谁的。
as to 有时用于表示 according to 的含义。例如：
They sorted the eggs as to size and color.
他们按照大小和颜色将鸡蛋进行分类。
as for 和 as to 都可用于句首，引出一个与前一个话题稍微有些不同的话题，但 as for 在语体上不如 as to 正式，并且着重话题的转换，也就是说，它所引导的是前面尚未提到过的新的事情，因此它不能用于文章的开头。另外， as for 有时表达轻蔑的语气。例如：
We had a delightful weekend in the country. As for the traffic， we had no difficulty.
在乡下我们度过了一个愉快的周末。至于交通，我们没有遇到任何困难。
Much pasture land is under water； as for the grain， most of that has been ruined.
大部分的牧场都进了水，至于谷物，则大部分都被冲毁了。
You can have a bed； as for him， he'll have to sleep on the floor.
有一张床给你，至于他，就只能睡在地板上了。
As for him， I know nothing.
至于他，我一点也不了解。
As for this subject， I couldn't remember.
至于这个题目，我记不起来了。
As for you， I never want to see you here again.
至于你，我永远也不愿在此见到你。
《高中英语语法-As to 与 As for 用法小结》由留学英语组编辑整理(www.liuxue86.com)