Input (grade 12): The Chinese contingent then laid siege to the city starting January 29, constructing a palisade and ditch, and employing siege engines and catapults.
Output (grade 9): Under Guo Kan's order, the Chinese counterparts in the Mongolian army then laid siege to the city, constructing a palisade and ditch, wheeling up siege engines and catapults. The siege started on January 29.