本ほん腰ごしを入いれる

expression, ichidan verb

to set about in earnest; to put one's back into; to make a strenuous effort

Idiomatic expression meaning to start doing something seriously and with full commitment, often after a period of hesitation or half-hearted effort.

• そろそろ本ほん腰ごしを入いれて勉べん強きょうしないと、試し験けんに間まに合あわない。

  I have to start studying in earnest soon, or I won't be ready for the exam.

• 会かい社しゃは新しん製せい品ひんの開かい発はつに本ほん腰ごしを入いれ始はじめた。

  The company has begun to put serious effort into developing the new product.