隐
=
急
+
阝
:
The pope (阝) and Maud Younger (y) both need to go to the bathroom in the encampment ((e)n3) urgently (急), but they both forgot the secret (隐) pass phrase so they cannot open the door.
之
=
丶
+
Z
:
Mnemonic symbol: Sooo sleepy... "zZz" (the character looks like a "Z"). James II of England (zh) fell asleep in front of the space station (Ø1). He sleeps on a big petal leaf (丶), making loud "zZz" (之) sounds.
心
=
乚
+
丶
:
Marie Curie (xi) uses a shovel (乚) to dig a hole in front of the encampment ((e)n1). She wants to bury her heart (心). To the side are three petal leaves (丶), with which she wants to cover it afterwards.