During the conference, I was surprised to cross his path after so many years.

cross 是动词，意思是"穿过、横过"，在这里表示"偶然相遇"的动作。 his 是代词 he 的所有格形式，表示"他的"。 path 是名词，意思是"小路、路径"，引申为"人生轨迹"或"活动路线"。 cross his path 这个短语字面意思是"穿过他的路径"，引申为"偶然遇见某人"，强调不期而遇的偶然性。