九校联盟

C9 League, alliance of nine prestigious Chinese universities, established in 1998

nine / 9

to proofread / to check / to compare

school / military officer / CL:所[suo3]

to check; to collate; to proofread

to ally / to unite / to join / (poetry) antithetical couplet

alliance / union / coalition

oath / pledge / union / to ally / league, a subdivision corresponding to prefecture in Inner Mongolia