Question

It was___fine weather___we decided to spend the day on the beach. A,such,that B,so,that为什么选A

Answer 1

such+a/an+ n.(可数名词)
such+n.(不可数名词)记住就好了。
希望可以帮到你。
参考资料【http://zhidao.baidu.com/link?url=Ux3klVhRqoYsTdRE6uaewpgXlA7omvAfEmsU_rBWWBnz5TJjJpVsD-h8SmyIykDK1pLwz03dhvCUp5IGpNbET_】
such与so的区别与用法
such与so的意思都是“如此，这样”。但两者用法根本不同，与what和how引导的感叹句相类似。

1、such后面主要是修饰名词。即：such＋a/an＋adj.＋n.或a/an＋such＋adj.＋n.。如果名词是不可数名词或复数名词，则不可以用不定冠词a或an。如：

①He has such a beautiful bike. We all go to see it.

②It's a such fine day. We al want to go to fly a kite.

2、so后面只能跟形容词或副词。即：和so＋adj.或adv.不过，so后面也可以跟名词，但该名词必须是单数可数名词。用法为：so+形容词+a或an+单数可数名词。如：

①The tiger is so big. And the cat is so small.

②She is so lovely a girl.

3、它们后面还可以与that从句连用。即：such…that和so…that意思是“如此……以致……”。如：

①She is such a clever girl that she can make much progress in math exam.

②His brother is so young that he can't go to school.

注：当名词前的形容词为表示数目的词时，such必须换成so。如：

①There are so many people that we can't go past.

②I ate so much food that I didn't want to go any farther.

注意这一句话：He is such a little boy that he can't read or write.(这一句话中的a little不是“一点”的意思，而是“一个小的”的意思，所以，前面仍然用such，而不用so。

Answer 2

固定搭配，such...that如此。。。以至于 天气很好所以我们决定去沙滩上度过