Some videos have been banned on the basis that they are too violent.怎么樣不同這里的that they are too violent是作同位語從句講解basis，還是作定語從句修飾basis？
basis= a reason for doing sth.
the basis = that they too violent = a reason.
所以這是同位關系。
that在從句中不作成分，符合同位語從句結構。
語法和語義二方面證明這是同位語從句。