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).
儿
=
丿
+
乚
:
Mnemonic symbol: "son" (儿) sounds similar to "Sun" like in "Sun Wu Kong", so it's gonna be represented by the monkey king. Albert Einstein (Ø-) and Sun Wu Kong (儿) are fighting in the space station's kitchen (-Ø2). Their weapons: Albert Einstein has a shovel (乚), and Sun Wu Kong has a banana (丿).
the five emphases, four beauties and three loves (PRC policy introduced in 1981, including emphasis on manners, beauty of language and love of socialism)
the Twenty-Four Histories (25 or 26 in modern editions), collection of books on Chinese dynastic history from 3000 BC till 17th century / fig. a long and complicated story