As the World Expo having been held for 153 years, Shanghai with a population of 17 million will become the first to host in the developing countries.请问as在这里引导的这个从句为什么要用非谓语，谢谢！
Summer （being） over, the students returned to school. Her face （being）pale with anger, she rose to leave. His first shot ( being) a failure, Tom fired again. It being a holiday, all the shops were shut.It being a hot day, we had better go swimming.为啥前三being能...
Quick
to claim credit, the prime minister is nowhere to seen when things go wrong这是《经济学人》的一篇文章副标题。主标题是：As
a second wave devastates India, Narendra Modi vanishes标题里的be可以省略，但这里省略be有点怪异。老师们怎么看？感谢！
You seem tobe dissatisfied with your present post，I don't think you judged your ability objectively when you applied forit,_____ you？A.did B.don't C.do D.didn't
Migrating to cities has become the choice for many people from the countryside."to cities"这里是做状语还是做migrating的补语呢？Exposure to high levels of radiation is harmful to your health.这里的介词短语可以看做是exposure的后置定语吗？
By 2050, Chengdu will be home of what local
officials say will bethe world's largest network of paths for people to walk
or bike.老师们请问what引导的从句是什么从句？我的理解是of...是home的后置定语，然后what从句是of的宾语从句吗？介宾结构？但是又觉得...
...elfare benefits explains why illegitimacy has also mushroomed among middle-class whites.他指出，没有哪个传统解释可以说明未婚先孕母亲现象的加剧，比如城里的男人没有工作，福利的增加用来解释为什么白人中产家庭的私生现象增长迅猛。老师...
...谢谢！This highly polite style is no doubt something that young women havebeen expected to "grow into"-atter all, it is a sign not simply of femininity, but of maturity and refine-ment, and its use could be taken toindicate a change in the nature of one's social relations...
...如下面的句子肯定是不定式作表语：Her work is to look after the children. 她的工作是照顾这些孩子。My aim is to start up my own company. 我的目标是开办一家我自己的公司。但下面的句子也属于不定式作表语吗？Such people are tobe pitied. 这种人...
... I had never read any story that attracted me as much. Ibegan to discover the world of
English literature and found that all the different books and stories I came
across opened my eyes to a different world from the one I had been familiar
with.这里的discover是答案，为什么不能选find呢...
A letter or telephone call comes from someone youhave not met, and you find yourself imagining what the person looks like, putting a face tothe hidden voice. 译文：一个你从没见过面的人给你寄来一封信或打来一个电话，而你不知不觉地想象着这个人是个什么样...
News corporation made its biggest acquisition since being split from the film and television parts of Rupert Murdoch's empire, by agreeing to buy Move, an online property listings firm, for $950m.请问老师，句中的since being split from 是介词+动名词宾语的结构吗？谢谢！
“Advertising often serves as an indicator for what society considers tobe socially acceptable and desirable at the time,” US marketing expert wrote on the Ad Council’s website.特别是what的用法弄不明白。