whimper|whimpered|whimpering

小狗被关在门外时，开始呜呜地哀鸣。

The puppy started to ___whimper when it was left outside the door.

受伤的小狗在角落里轻声呜咽着。

The injured puppy ___whimpered quietly in the corner.

受伤的小狗在角落里低声呜咽着。

The injured puppy was ___whimpering softly in the corner.