怠おこたらずに

adverb

diligently; without fail; carefully

Used to describe doing something consistently and attentively, without neglecting it. Often appears in formal or written contexts.

• 毎まい日にち怠おこたらずに練れん習しゅうすれば、必かならず上じょう達たつします。

  If you practice diligently every day, you will definitely improve.

• 健けん康こうのために、怠おこたらずに運うん動どうを続つづけている。

  For my health, I continue to exercise without fail.