解析四级英语语法题1.By the time he arrives in Beijing,we ( )here for

解析四级英语语法题
1.By the time he arrives in Beijing,we ( )here for tow days.
A.have been staying B.have stayed C.shall stay D.will have stayed
2.As a public reiations officer,he is said( )some very influential people.
A.to have been knowing B.to be knowing C.would have known D.to know
3.Our hopes ( ) and fell in the same instant.
A.arouse B.arose C.raised D.rose
帮忙把第3题的四个词区别一下
第二题答案是C