Xiao Chen was refused entry to the ancient book library by the staff because he did not have the status of a graduate student  Xiao Chen showed the pass of the rare book library of ancient books and said: According to the regulations, I can enter the ancient book library
The rule of it is that non-graduate students are not allowed to enter the ancient book library, and only those who have a pass for the pass of the rare book library of ancient books can enter the rare book library of ancient books
You cannot enter the rare book library of ancient books unless you have a pass for access to the rare book library of ancient books.