A: First look at why he didn't energetically resist the Japanese. After Zhang Zuolin was killed by the Japanese on 4th June, 1928, Zhang Xueliang was at a crossroads. The Japanese attempted to keep him away from the Nanjing government and offered to provide military and economic assistance to help him resist the Nanjing government's Northern Expedition.
答：先看張學良為何未積極抗日，民國十七年六月四日，張作霖被炸死後，張學良面臨十字路口，日本人逼他不得和南京政府合作，提出在軍事、經濟上予以全力支援，幫助他抵抗南京政府的北伐軍。