1、He spoke so fast that i could not ( ) what he said.

1、He spoke so fast that i could not ( ) what he said.
A:touch B:catch C:hear D:find
2、He has not decided（ ）.
A：if he will go on a trip to Hainan.
B：if he goes on a trip to Hainan.
3、time passed quickly and three months went by ( ) we knew it.
A:when B:after C:before D:till
4、the result of the experiment was very good ( ) we had not expected.
A:when B:that C:which D:it
5、when and where to build the new factory ( ) yet.
A:is not decided B:are not decided
C:has not decided D:have not decided
我这里有答案 可是不知道为什么这样选,

1.B
句意为：他说得很快,以至于我不能理解他说的话.
2.A
宾语从句所表达的动作相对于主句动作来说还未发生,故用将来时来表达将要发生的动作.
3.C
句意为：时光飞逝,不知不觉3个月已经过去了.
4.C
此句话应在good后加上逗号“,”,此题选C,Which 在此处引导非限制性定语从句,指代主句所表述的内容.句意为：实验结果非常好,这一点是我们事先没有想到的.
5. A
此题句中主语为 动词不定式短语,谓语动词应为单数,when and where作状语修饰 to build the new factory ,主语不应受when and where的影响.另外主语 to build the new factory 和谓语动词decide之间是动宾关系,故应使用被动语态.所以选择A.至于yet完全可以用于一般现在时,如：Our holiday isn't for weeks yet.