First of all, it is determined that the deceased is Zhang in the study. Only osawa Ming can enter the study, but osawa Ming has no motive to kill Zhang, so it is possible that he killed Zhang by mistake. Zhang's body shows that he died of respiratory failure, and both Da Zemin and Da Wen's botulinum toxin can cause respiratory failure. Whoever knows this is probably the murderer. ?

If Da Wenjing wants to get rid of suspicion, she must find out that Zhang Chunlai is a nurse in a medical beauty hospital. She can also learn that high doses of botulinum toxin can kill people. She killed Zhang by mistake in order to kill osawa Ming, but the broken vase on the ground locked the possibility of poisoning at home at that time.

At that time, there were only two people in the room, Jen and Jing Dawen, but Jen had no relevant knowledge and only Jing Dawen poisoned them. Da Wenjing poisoned Ahua, but no one ate it. As a rural woman, she was afraid of wasting all the food, which led to Zhang's death.

Brief introduction and evaluation of On the Road;

The motive of Zhang's false suicide is that he knows that his "curse of bleeding" is dying, and in the "temple" stage, Zhang knows that Ahua will be sent to a mental hospital, and in the "home" stage, he is humiliated by Ahua's language, so he wants to do something for Ahua, so he wants to commit suicide by false suicide ("a rope with four rings in the clue",

In fact, it is a rope with five rings. One ring is around the neck, and the others are around the arms, upper chest and lower chest, which seems to be suicide. Gravity is entirely borne by the body, and then the rope at the back of the neck can be cut. ) Go to Da Wenjing's room at night to dress up as a ghost, and make sure Jane doesn't speak, so she doesn't need to be sent to a mental hospital.