6.Most environment problems exist because adequate measures for preventing them ( A ) taken in the past.A.were not B.had not been 8.The professor ,( A ) as a splendid speaker,was warmly receiver by the stuclents.A.known B.to be known C.having known9.

6.Most environment problems exist because adequate measures for preventing them ( A ) taken in the past.A.were not B.had not been 8.The professor ,( A ) as a splendid speaker,was warmly receiver by the stuclents.A.known B.to be known C.having known9.
6.Most environment problems exist because adequate measures for preventing them ( A ) taken in the past.
A.were not B.had not been
8.The professor ,( A ) as a splendid speaker,was warmly receiver by the stuclents.
A.known B.to be known C.having known
9.He is said ( C ) for five years.
A.to have died B.to die
C.to have been dead C.dead
10.Most of people ( A ) to the party were famous scientists.
A.invited B.being invited
就是不知道为什么不选答案之外的选项?

6.Most environment problems exist because adequate measures for preventing them ( A ) taken in the past.A.were not B.had not been 8.The professor ,( A ) as a splendid speaker,was warmly receiver by the stuclents.A.known B.to be known C.having known9.
6.意思是：许多环境问题仍存在,因为还没有足够的措施来阻止.
且 in the past是指：过去的一段时间,用一般过去时,而B选项是过去完成式,是表示过去的过去.
8.The professor 是主语
The professor was warmly receiver by the stuclents.这是一个完整的句子,known as a splendid speaker 被大家所知道的一个著名的演说家 ,这是过去分词作后置定语,也有固定词组:be known as 因什么样的名人而出名
还有你是不是打错啦,receiver应该是received啊.
to be known 是被动语态,例如：He is so famous to be known!
他太出名了而被很多人认识.
having known是指已经被人认识,一般指在之前已经认识了.
9.for five years表示已经持续五年了,用现在完成时表示持续了一段时间,
be said to do 是 据说 的意思,可以排除to die和dead
而dead是形容词,die是动词,就如：如果表示状态的话,当然用"She is dead"比 She died 频繁的多.用dead更好点,因为文中有for + 一段时间表示了状态.所以不选A.
10.这个句子属于定语从句.还原原句：Most of the people who were invited to the party were famous scientists.invited to the party 是定语从句修饰 the people .句子结构明白后.而这个句子的逻辑主语也就是和主句主语一致,且谓语动词是be动词的时候 were invited 句子的主语和谓语可以省略.（这种句子有专门的叫法,叫无动词从句）.
本文的who were 被 省略了的 .invited 是表状态,就是用过去分词,这是过去分词的一种用法 ,本文用的是过去式,表明已经被邀请的人.
而being invited 是正在被请,带有进行时的意味
可以比较一下：
to be done和being done如果做后置定语的话,两者区别如下：
被修饰词 + to be done “将要被...的...”,即被动的动作尚未发生；
被修饰词 + being done “正在被...的...”,即被动的动作正在进行.
如：the meeting to be held tomorrow 明天将要举行的会议；
the meeting being held now 现在正在举行的会议

6 in the past 在过去 用一般过去式
8. 过去分词做定语
9 be said to do 据说。。
for + 一段时间 用现在完成时
10 同8题过去分词做定语 修饰people 被邀请的人

6.因为这只是个客观的事实——没有采取恰当的措施，所以该用什么时态就用什么时态就行了，句末in the past 说明用一般过去式！
如果题目把exist 改成are solved，则要选B。因为过去实施的措施对行政造成了影响——环境问题解决了。
8.可以理解为定语从句，只是省略了“who is”，或者是过去分词做定语。然后就是要知道“be known as”——作为···而闻...

全部展开

6.因为这只是个客观的事实——没有采取恰当的措施，所以该用什么时态就用什么时态就行了，句末in the past 说明用一般过去式！
如果题目把exist 改成are solved，则要选B。因为过去实施的措施对行政造成了影响——环境问题解决了。
8.可以理解为定语从句，只是省略了“who is”，或者是过去分词做定语。然后就是要知道“be known as”——作为···而闻名这个词组就
能把答案轻松选出了！
9.这道题不应该有疑问的吧？be said to ```,排除D；然后应为已经死了5年了，所以用完成时，然后dead是形容词，所以选C。
10.这道题就是过去分词做定语了，invited to the party做people的定语。B.指正在被邀请，而后面were明显可以看出是过去了，所以排除。

收起

A A C A