核心问题
He bought the stock for me. 请问句中 for me 是表示“给我”，还是“替我”？
词典解答
就孤立的句子而论, for me 既可能指“给我”, 也可能指“替我”, 因为 for 的这两层含义在这里都适用。
(a)他给我买了股票。(He bought the stock; the stock was for me. 或 He bought me the stock.)
(b)他替我买了股票。(He bought the stock; he did it for me.)