齰

昔 = 井 + 日 : Mnemonic symbol: From 奶昔, milkshake

In former times, Marie Curie thought that at the end of every day, the sun falls into a well and therefore the light goes off. Nowadays as she is floating in front of the space station, she finds that she was right: as in the former times, every evening the sun goes into the well to fetch herself a milkshake.

齿 = 止 + 凵 + 人 : Charlie Chaplin (ch) has an aching tooth (齿), and Neanderthal Man (人) is about to help him take it out using an electrical barrier (止) in the space station (Ø3). They attached the barrier to the tooth and as Neanderthal Man will plug it into the receptacle (凵), the barrier will pull out the tooth.