The editor spent three months meticulously proofreading the novel.
Tips
usage
Abbreviation of 精确校对 (jīngquè jiàoduì, "precisely proofread"). Common in publishing, especially on classical/scholarly editions where 精校本 (jīngjiào běn) marks an authoritative collated version.
mistakes
校 here is jiào (4th tone, "to check / collate"), NOT xiào ("school"). The character has both readings — pick by meaning.