第一，Is this （the） train for Shanghai？书上说名词中心词有后置修饰语，所以这是前照应特指，所以填the.
In__a__
review of 44 studies, American researchers found that .....这个难道不是前照应特指？为什么填a呢？
第二， He has a good knowledge of many
foreign languages,and one of them is English which is （the） lannguage spoken by many people in the world.这个为什么不是a，一种被世界上很多人说的语言。
