二來

二 = 一 : Mnemonic symbol: a capacitor, because the two strokes remind me of the symbol in electrical drawings. Albert Einstein (Ø) is experimenting with a capacitor (二) in the space station's bathroom (Ø4). He finds that it's uncomfortable to discharge a capacitor using two flutes (一).

來 = 从 + 木 : Mnemonic symbol: mailwoman. Sir Lancelot (l) is visiting the mailwoman (來) in the airplane's kitchen (ai2). As a gift, he brought a Christmas tree (木) decorated with rubber chicken (从).

来 = 丷 + 未 : Mnemonic symbol: mailwoman. Lancelot (l) is super happy that his inflatable crocodile (丷) and live size Ai Weiwei (未) puppet finally arrived (来). The mailwoman (来) delivered them straight to the kitchen of the airplane (ai2).