音階

音 = 日 + 立 : Mnemonic symbol: a loudspeaker.

音 = 日 + 立 : Maud Younger and the Sun opened a pop-up store in front of the encampment. They sell vases and advertise them using loudspeakers, playing loud music and dancing to it.

阶 = 介 + 阝 : The pope (阝) sentenced Joan of Arc (ji) to death and wants to shoot her to outer space using a rocket (介) in front of the elevator (e1). He doesn't have a proper launch ramp, so he just uses some stone stairs (阶).