to exist; to be alive / (of sb or sth) to be (located) at / (used before a verb to indicate an action in progress)
在
=
一
+
亻
+
土
:
Zorro (z) and Rosa Luxemburg (亻) exist (在) in the airplane's bathroom (ai4). Rosa is in the middle of balancing a flute (一) on her head and on a pile of clay (土). Zorro uses his rapier to inscribe "Z" into the flute, so as to mark that the pronunciation of "在" begins with "z".
真
=
具
+
十
:
Mnemonic symbol: a replicator. It generates real and genuine things out of nothing. Looks like a microwave with a cross as antenna. James II of England (zh) broke his replicator (真) in front of the encampment ((e)n1): the cross (十) on the top is broken. Using his toolbox (具), James II of England tries his best to fix it. Fortunately he has a genuine, authorized, real (真) replacement cross.
空
=
工
+
穴
:
In front of the engine, Karl Koala found some very special cave paintings. Using steel beams he constructs a protective cover. He also installs air conditioning to make the best environment possible to preserve the cave paintings.
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.