He heard the clattering sound of the machine being hit.

He always supports my opinion.

Free radicals play an important role in chemical reactions.

This medicine contains strychnine.

He called the novel a work of effort.

Understanding dynamical systems is an important part of physics.

He drew his own original character and shared it on social media.

Rikishimai is a traditional performance performed with a mask.

He made strenuous efforts to pass the exam.

He continued his strenuous efforts to pass the exam.