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log
dace (Tribolodon hakonensis)
test subject (of human experiments performed by Unit 731 during WWII)
丸太が川面に浮かんでいた。
A log was floating on the river surface.
丸太を積んだトラックが通った。
A truck loaded with logs passed by.
子どもたちが丸太の上でバランスをとって遊んだ。
The children played balancing on a log.