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He was diagnosed with congestive heart failure.

The Atlantic puffin is one of the most commonly seen birds in the North Atlantic.

He was considered the wisest among the ignorant, like a bat in the land of the blind.

The Papua fire-eating bird, with its unique appearance, is a bird you won't forget once you see it.

We are aiming to kill two birds with one stone with this plan.

He is exactly in the state of 'A frog in a well does not know the vast ocean.'

He spoke of his big dreams, saying, 'How can a sparrow understand the ambitions of a swan?'

His father fell into a persistent vegetative state due to a traffic accident.

Basic oxides react with acids to produce salt and water.