膝ひざを落おとす

expression, godan verb (-su)

drop to one's knees; sink to one's knees

Describes the physical action of lowering oneself onto the knees, often from a standing position. Can be used literally or figuratively for a sudden collapse.

• 疲つかれ果はてて、その場ばに膝ひざを落おとした。

  Exhausted, I dropped to my knees on the spot.

• 衝しょう撃げきの知しらせに、彼かれは思おもわず