"bottom mochi": the result of falling backwards and landing on one's rear

play, amuse oneself, enjoy oneself / spend one's time idle, do nothing / for an item not to be in use, be spare or idle

traditional folk song of Amami / (more broadly) traditional folk song of Okinawa

park

To do something completely (unintentionally); cannot help doing

indicates that something undesirable was done or happened

to close / to finish, do something completely / to put away, to put an end to / is, or was (with conjugation), done completely / happens, or happened, unexpectedly / is done with difficulty

used in response to a failure or mistake: dang, shoot, darn it

sister city

person of extensive knowledge