橡實

橡 = 木 + 象 : Marie Curie (xi) wants to plant some oaks (橡) in the anglepod's bathroom (ang4), so she had the KFNB Elephant (象) transport young oaks to the bathroom. In exchange she provides the train with a lot of Christmas trees (木) to be used as fuel for the steam engine.

实 = 头 + 宀 : Sherlock Holmes welcomes professor Skull just inside the entrance of the space station. Professor Skull has not a complete head but only a skull, and a solid understanding of solid state physics. She really is an honest person and still wears her graduation cap.