四时

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).

时 = 寸 + 日 : Mnemonic symbol: a giant pocket watch.

The sun (日) asks Sherlock Holmes (sh) out for a coffee in the space station's kitchen (Ø2). Looking at his pocket watch (时), Sherlock sees he has time, winks and "thumbs up" (寸).