the position of captain.

【问】 He was raised to the position of captain.

captain是个可数名词，为什么在这里不加冠词?

【答】 在the position of A，the role of A和the post of A这些结构中，如果A表示独一无二的身份或者职务，就可以省略定冠词。请对比：

1. My sister has got a position as a cook. (JED)

我姐姐找到一个作厨师的工作。

2. We might get you a post of a waitress. (Galsworthy)

我们有可能给你找到作女招待的工作。

3. After declining the post of Secretary of State he nevertheless found himself taking onthe role of unofficial adviser to the President. (CGEL)

拒绝了国务卿的职务后，他却发现自己成了总统的非官方顾问。

4. be given a post as general manager(ALD)

被授与(获得)总经理之职务

5. He assumed the role of interpreter for the group. (MD)

他但任了该团的口译员的角色。