请先阅读下面短文，掌握其大意，然后用方框中所给词的适当形式填空。每个词限用一次。 that, dangerous , cry , hospital , pull , run , hold , save , quick , possible Mr. Black was once a policeman. He was a kind person. He liked to have a walk in the park after breakfast. It was very cold on a winter morning. Mr. Black was walking along the street when he heard a 【1】 for help. He turned around but could see nobody. He stopped and looked here and there. At the moment, a boy 【2】 up to him. The boy was in such a hurry 【3】 he couldn't say a word except