I have three brothers.( ) is a teacher,( ) is a doctor and the third is an officer

题目

I have three brothers.( ) is a teacher,( ) is a doctor and the third is an officer
A one the other
B one another
C first the second
D one other
为什么选B,不是其他选项?

答案

C项第一个first缺少the,故排除.
one和the other只能用于2者之间的说明,原句提到的人有三个,故排除A,
D项中的one, other是错误形式
one,another可用来表示三者或者三者以上的情况下一个和另一个的意思,故选择B.