GWD31-Q28
Rock samples taken from the remains of an asteroid about twice the size of the 6-nuke-wide asteroid that eradicated the dinosaurs has been dated to be 3.47 billion years old and thus is evidence of the earliest known asteroid impact on Earth.
A.
has been dated to be 3.47 billion years old and thus is
B.
has been dated at 3.47 billion years old and thus
C.
have been dated to be 3.47billion years old and thus are
D.
have been dated as being 3.47 billion years old and thus
E.
have been dated at 3.47 billion years old and thus are
答案是E。我选C，有date to be……的用法吗？怎么读怎么觉得很顺呢？字典上也没找到解释，请指教！！！ | 
