不
=
丆
+
卜
:
Bruno Bear (bu) is setting up a wind wheel (丆) with a voodoo staff (卜) in the space station's bathroom (Ø4). He also puts a "forbidden" sign (mnemonic symbol for 不) on it, to make clear that it may not (不) be stopped.
外
=
夕
+
卜
:
There's a hole in the wall of the airplane's bathroom (ai4), and from outside (外), a bat (夕) wants to enter. Willy Walrus (w) is very afraid of bats, so he does his best to hinder the bat from entering with a voodoo staff (卜).