He was wearing an ancient mourning dress.

His jet exceeded the speed of sound, causing a sonic boom.

He raised his hand and asked a question.

Plants of this kind are collectively referred to as 'cacti'.

His actions destroyed his family's happiness.

He was known as a bully at school.

This is a 六角四片四角孔ねじれ正多面體, in other words, a muoctahedron.

This is a model of a muoctahedron.

He exhausted his strength to finish the work.

Sentarou fell asleep while watching TV.