whistling
词形变化：
动词过去式: whistle-stopped | 动词过去分词: whistle-stopped | 动词现在分词: whistlestopping | 动词第三人称单数: whistle-stops |
whistling
词形变化：
动词过去式: whistle-stopped | 动词过去分词: whistle-stopped | 动词现在分词: whistlestopping | 动词第三人称单数: whistle-stops |