生物材料

生 = 牛 + 一 : Mnemonic symbol: a cradle.

Sherlock Holmes (sh) comforts a crying baby bull (牛) in a cradle (生) in front of the engine ((e)ng1) and plays him a tune on a flute (一).

物 = 勿 + 牛 : Willy Walrus (w) wants to become a physicist (物) and does research about dark matter (物) in the space station's bathroom (Ø4). His motivation is to become a super villain and rule the world. Just as he is about to have a breakthrough, a huge black ox (牛) flying with the help of bat wings (勿) hits Willy with an oxerang and takes away the dark matter, saving the world.

材 = 才 + 木 : In the airplane, the King of Chu investigates a Christmas tree with his secret X-ray vision super power. He can see that the material the tree is made out of is not timber; instead, he sees that the tree has been 3D printed.

料 = 斗 + 米 : Li Qingzhao sees the matador fighting a sack of rice in the aorta's bathroom. At least she thinks she is fighting the sack of rice as he is repeatedly stabbing it. Truth is that he is working as inspector and taking samples of the rice to inspect the material.