这天下午，在天津东站，我和千余名天津市支边的中学生登上赴黑龙江的知青专列。
B-Time I-Time I-Time I-Time O O B-Location I-Location I-Location I-Location O B-Person O B-Person I-Person I-Person B-Location I-Location I-Location O O O B-Person I-Person I-Person O O O B-Location I-Location I-Location O B-Person I-Person B-Thing I-Thing O