GWD-30-39

In addition to being China’s first administrators, in the sense that they developed a coherent bureaucracy for their empire, the first literate culture in East Asia were the Shang, and they were well known for crafting ornate bronze ritual vessels.

1. the first literate culture in East Asia were the Shang, and they were well known for crafting
                       （核心词不是人，排除）
2. the first literate culture in East Asia were the Shang, well known as the crafters of
                       （核心词不是人，排除）
3. the Shang, as the first literate culture in East Asia, is well known for its crafting
4. the Shang were the first literate culture in East Asia and are well known as the crafters of
5. the Shang were the first literate culture in East Asia and well known for its crafted

答案D,我想知道为什么D中不用一般现在时而用过去时,因为也算是科学事实了.再说前句和后半句的现在时are不并列呀

牛人指点,谢谢

首先这个跟科学事实还是不同的， 所谓的科学事实应该为“真理”（留心“真理” 和”事实“ 的差别哦） 比如：地球绕太阳转，地球是圆的（你体会一下，”真理“ 其实是没有时间限制的）事实不一样， 事实可以有时间限制哦。 所以Shang在（古代） 是最大的administrators 这个是过去发生的事实， 他们现在普遍被认为...

"The Shang were the first literate culture in East Asia and are well known for crafting ornate bronze ritual vessels. They were also China's first administrators, developing a coherent bureaucracy for their empire, and were able to marshall the human labor required to build rammed earth walls such as those found at the Huanbei
                Shang
                City"  you could find the original sentence on internet

請問,為什麼要用複數were and are? thnaks!