双曲面

双 = 又 : Sheldon shrimp is dual wielding boxing gloves in front of the anglepod.

双 = 又 : Sheldon shrimp is dual wielding boxing gloves in front of the anglepod.

曲 = 囗 + 卄 : Mnemonic symbol: a harp. Cupid (qu) is playing a harp (曲) in the space station's living room (Ø3). He's sitting on a big enclosure (囗), playing the harp (曲) and wielding a double axe (卄) at the same time.

面 = 丆 + 囬 : Mnemonic symbol: a spray flask with one of these liquids which make a surface super slippery.

In the anthill's bathroom (an4), Marilyn Monroe (mi) wants to set up a wind wheel (丆) on top of a closet (囬). Just as she tries to fix it she slips and falls down, the wind wheel crashing on the floor. She didn't notice that somebody used a can of non-stick coating (面) on the closet's surfaces (面).