In May 1941, Li Shaotang explained to Shen Congwu his interactions with the Communist Party member Lou Mingyuan as “Sundial”. He also expressed his intention to stay in the military and serve the party-state in biochemistry.Later, Li Shaotang entered the Qingpu training class and joined the Chongqing station after the training.Shen Congwu told Li Shaotang that after he got in touch with the Communist Party Huo Mingda, the radio stations related to “weed” became obviously active.But why didn't “Weeds” show up and take action during the polygraph test?