1.----night coming om,they set off for home.A as B with Cby

1.----night coming om,they set off for home.A as B with Cby D all
（为什么选with,它们的用法有哪些不同.）
2.------impressed me most was his honesty and bravery.A that B what who D all (选什么 ,为什么)
3.I didn't heart you clearly .It’s too noisy here.ARepeat B Once again CPardon?DSo what?(为什么选 C A.B.D哪里用法不对?)

第一题选with是因为with的复合结构,下边叙述中的三：
with复合结构的构成
with+宾语+宾语补足语,构成with复合结构,宾语可以是名词或是代词,宾语补足语可以是介词短语、过去分词、现在分词、形容词、动词不定式、副词.且with后面的宾语与其后的宾语补足语有逻辑上的主谓关系.
1)With+宾语+介词短语
He was asleep with his head on his arms.
2)with+宾语+过去分词(宾语与宾补之间是被动关系)
All the afternoon he worked with the door locked.
He lay in bed with his head covered.
3)with+宾语+现在分词(宾语与宾补之间是主动关系)
With winter coming on,it's time to buy warm clothes.
4)with+宾语+todo(不定式做宾补有“将来”的含义)
I can't go out with all these dishes to wash.
5)with+宾语+形容词/副词
第二题选B what,这个句子是what引导的一个主语从句做主语.what impressed me most was his honesty and bravery.what在这个what impressed me most中做句子成分,如果这个主语是一个完整的句子就可以用that来替换,但是这个句子缺少句子成分,只能用what来做,因而这个题目选what
第三题选C pardon是因为没有听清而表示询问的词,根据句子情景,表明是因为外界环境太吵,所以没有听清,因而需要对方重复一下,所以用pardon?,其余的在口语的日常交际中用不到,都是正面的问could you please repeat it 之类的,so what 是一种语气很乖张的口气词,有反问的语气,意为“那又怎么样?”
再问： 能和我讲一下那个第一题中 as 和 by 的用法。并讲一下主要的区分吗？谢谢
再答： as用法小结： 　　一、as用作介词，意为“作为、当作、以”。例如： 　　1. Each language seems to be the most important to those who speak it as their mother tongue. 　　2. Today, Abraham Lincoln is regarded as one of the greatest American presidents. 　　3. They set up a state of their own, where they would be free to keep Negroes as slaves. 二、as用作关系代词，引导定语从句 　　1. 引导非限制性定语从句，可用来指代主句所叙述的内容，译为“这一点、这件事”。例如： 　　As we have seen, oceans cover more than 70 per cent of the earth. 　　2. 引导限制性定语从句，常用在固定搭配“such… as…, the same…as…”等中。例如： 　　He is doing the same work as I am. 　　Such a film as you described should not be shown at all. 三、as用作连词，引导状语从句 　　1. 引导原因状语从句。例如： 　　As you weren’t there I left a message. 　　2. 引导时间状语从句。例如： 　　As he grew older he lost interest in everything except gardening. 　　3. 引导让步状语从句。例如： 　　Young as he is, he already knows what career he wants to follow. 　　4. 引导方式状语从句。例如： 　　Why didn’t you catch the last bus as I told you to? 四. as与其他词结合，构成固定搭配。例如： 　　as a matter of fact, as usual, as well, as well as, so as to… 　by的用法小结： 1、介词 prep. 在…旁；靠近 2、 介词 prep. 经过 3、介词 prep. 用；靠；通过 。 4、介词 prep. 不迟于 5、介词 prep. 通过；沿着 6、介词 prep. （表示作者）被；由 7、介词 prep. （指交通等）乘；用 8、介词 prep. 在…情况下；在…时间 9、介词 prep. （表示部分）在…部位 10、副词 adv. 在旁边 11、副词 adv. 从旁边经过 by详细用法见参考资料