beaver away

Etymology
From the metaphorical image of a person working as industriously as a beaver building its dam.

Verb

 * 1)  To work hard at a task.
 * She won't be going out much, as she's beavering away on her thesis.

Translations

 * Finnish:, ,
 * French:
 * Georgian: მუყაითობს, გარჯა, ბეჯითობა