工地

工 = 二 + 丨 : Mnemonic symbol: a steel beam, since 工 looks like the cross section of a steel beam.

Gitta Giraffe (gu) is working a shift in front of the engine ((e)ng1). Her job is to melt dinosaur bones (丨) so that they can be disposed off easily. To melt the bones, she is shorting a huge capacitor (二) with a steel beam (工) which consequently heats up to a bright glow. Using the glowing hot steel beam she can melt the dinosaur bone easily.

地 = 也 + 土 : Dorothy Gale (di) hates the cleanliness of the space station, so she used an excavator (也) in the space station's bathroom (Ø4) to dig a pile of dirt (土) out of the ground (地) for a mud bath.