亨利、戴维、梭罗(1817___1862)是美国十九世纪自然主义作家的先驱，到访他的故居，是今年在波士顿儿子家过年意外的收获。
B-Person I-Person I-Person I-Person I-Person I-Person I-Person I-Person B-Thing I-Thing I-Thing I-Thing O O O O O O O O O O B-Location I-Location B-Time I-Time I-Time I-Time B-Abstract I-Abstract I-Abstract I-Abstract B-Person I-Person O B-Person I-Person O O O B-Person O B-Location I-Location O O B-Time I-Time O B-Location I-Location I-Location I-Location I-Location I-Location O O O O O O O O