Swallow here refers to the bird, not what one does when eating or drinking.
Mnemonic
[y-] Yoshi is in the [4] bathroom of the [-an] pawn shop where he is feeding a 燕 swallow that is living there at the top of a 北 north pole in the corner. Yoshi puts a 廿 bucket on top of a 灬 burner to heat up some food, then puts it carefully in the 燕 swallow's口 mouth at the top of the 北 north pole to feed it.