这位政治家以极大的热情谈论着他的改革计划，感染了在场的每一个人。

The politician spoke about his reform plans with such fervor that it moved everyone present.

fervor 是名词，来自拉丁语 fervere（沸腾、发热），指"强烈的热情或激情"，常用来形容演讲、信仰或情感方面的热烈状态。