Robert is said___abroad,but I don't know what country he studied in.a.to have studiedb.to studyc.to be studyingd.to have been studying.这个是现在完成时么?为什么a选项不是to have been studied?什么时候要用上"been"这个单词的?

Robert is said___abroad,but I don't know what country he studied in.
a.to have studied
b.to study
c.to be studying
d.to have been studying.
据说罗伯特在外国学习，可是我不知道他在哪个国家。
选A。
have done已经做过
have been done ，been是be动词的过去分词形式，表示被动
你想，他在外国学习，是被学习吗？不是吧。主动的学习。
所以不用加been.
完毕。

Reported speech:
Robert is said to have studied abroad,but I don't know what country he studied in.
第一个动词 is said to ...就是完成时 past tense passive ，but i don't know which c.he studied in..也是 past tense,所以用 A ； 其它他的都不会用：
He is said to be studying in France (and he's still there, in France) = they say he is studying in France
He is said to have been studying in France for near five years, and he still has not graduated.
http://www.englishpage.com/verbpage/presentperfect.html
http://www.englishpage.com/verbpage/presentperfectcontinuous.html

a

正确答案：A
首先，A不能用to have been studied，因为这是被动语态，而学习是Robert的主动动作，另外，不选D是因为后面半句的提示可以说明这是过去发生的事情，所以不能用现在完成进行时。

这个题很有意思,很不错,很容易选错C.
这个题的正确答案是A
这个题的关键是句未的动词studied,是过去式,说明Robert已经不在国外学习了,已经完成了该动作,符合完成时态的定义.这个题如果把studied改为studies,那么这个题就选C,表示正在进行.
你问的问题,什么时候要用上been,这很简单,been+过去分词,表示被动语态的完成式.而题目中,是主动语态,不是被动语态,所以不用been.