His grandfather is supposed（）for New York last Friday. A. to have left B. to leave C. to have been left D. to be leaving

本题考查动词短语“be supposed to”的用法及动词完成式的语境应用。解题关键在于：

1. “be supposed to”后接动词原形，但需注意时间状语的搭配；
2. 当动作本应完成但实际未发生时，需用“to have done”结构；
3. 通过时间状语“last Friday”判断动作发生在过去的某个时间点之前，需体现“本应完成”的语境。

选项分析

A. to have left

• “to have left”表示“本应在过去的某个时间点前离开”，符合“last Friday”这一时间状语，强调动作本应完成但可能未完成。
• 例句：He was supposed to have finished his homework yesterday.

B. to leave

• “to leave”表示“本应离开”（一般情况），但未体现“last Friday”这一时间点前的完成性，语境不符。

C. to have been left

• 被动语态与主语“grandfather”（主动行为）矛盾，排除。

D. to be leaving

• “to be leaving”表示“即将离开”（进行时态），与“last Friday”矛盾，排除。