to pile up / to heap up / a mass / pile / heap / stack / large amount
堆
=
土
+
隹
:
Doggy Dog (du) is digging for a bone in front of the Eiffel Tower (ei1) and in the process he is piling up (堆) a huge pile of dirt (土). After Doggy Dog gave up the sparrow (隹) comes to sit on the pile, since she thinks it is quite a nice place.