有一读者问： 《英语世界》有这么一个句子：
(1)With them safely achieved, there may no longer be that urge to be curious and constantly learn more that is so essential.
此句第一个that从句的主语是什么？ 尤其是and constantly learn的主语是什么？
that在此不是连词（它并未引导一个从句），而是指示代词，用作定语，修饰名词urge。to be curious and constantly learn more that is so essential这两个并列的不定式短语是修饰urge的定语。名词urge常后接不定式，再如：
(2)We all have the urge to learn English.
(3)They have a strong urge to communicate.
