within / among / in / middle / center / while (doing sth) / during / (dialect) OK / all right
中
=
丨
+
口
:
Mnemonic symbol: a dart board, because you always try to hit the center.
Julian Giant Squid (zhu-) is throwing dinosaur bones (丨) as darts on a dart board in front of the engine ((e)ng1). To make it a bit more difficult he's throwing mandarins (口) into the air as well and skewers them up right in the center (中 is a mandarin skewered on a dinosaur bone) in mid flight with the dinosaur bones. He's still able to consistently hit the center (中) of the dart board.
二
=
一
:
Mnemonic symbol: a capacitor, because the two strokes remind me of the symbol in electrical drawings. Albert Einstein (Ø) is experimenting with a capacitor (二) in the space station's bathroom (Ø4). He finds that it's uncomfortable to discharge a capacitor using two flutes (一).
illness / CL:場|场[chang2] / disease / to fall ill / defect
病
=
丙
+
疒
:
In engine's bathroom Brunhilde is proudly inspecting her bronze medal. She got it in a contest about having the craziest sickness by painting a colorful rash on her face.