old documents / (in palaeography) historical documents written to convey a specific intention between a sender and receiver; generally inclusive of written material through the mid-19th century

paleography

(archaic) explanation (of meaning); interpretation

Could you please do something for me? (polite form)

to inform, to teach, to instruct / to tell

Tachysurus nudiceps, a species of catfish.

solution, untie

divide; split; separate / untie; loosen; relax; remove / make clear; explain / understand; comprehend / opinion; explanation; solution

explanation; interpretation / (mathematics) solution / answer; reply (to a given question or problem)

teachings, doctrine, lesson