单选题 17.  I was in some doubt as to whether the detective had ______ us accidentally on his way out of the town or if he'd been deliberately tasked.
【正确答案】 B
【答案解析】 考查动词短语辨析。crash into意为“撞到……上”；bump into意为“撞见，偶然碰见”；puzzle about意为“苦思冥想”；fall against意为“摔倒”。本题是“偶然碰见”之义，故选B。
   我有一些疑问，侦探是在出城镇的路上偶然碰见了我们，还是他被特意委以任务。