四
=
儿
+
囗
:
Mnemonic symbol: a four-leaved clover. Socrates (s) is working out in the bathroom of the space station (Ø4). He's lifting four (四) wooden boxes (囗), and wonders why they are so heavy. He doesn't know that inside one of the four boxes, the monkey king (儿) is hiding and secretly laughing at him - until the monkey king comes out and surprises Socrates with a four-leaved clover (四).
氵
=
⺀
+
㇀
:
Mnemonic symbol: a bottle of water. Sheldon Shrimp (shu) enjoys a bottle of water (氵) in the Eiffel Tower's living room (ei3). The got the water by scratching (㇀) a blossom (⺀) and catching the leaking dew in a bottle.