실전편 4회 37번
with regard to the use of between, what the careful writer must ask himself or herself is not how many elements are involved but rather what is the relationship they bear to one another.

if the relationship involves sets of two, the word between is appropriate, no matter how many elements are involved.

for instance, it is proper to speak of a treaty between the four powers that have nuclear weapons because the treaty binds every power to each of the three others.

among would not be improper, but it is a vaguer, more general word.

likewise, it would be proper to say that a triangular plot of land lies between three points and not entirely proper to say it lies among three points.

as another example, there is a helicopter service between (not among) kennedy, la guardia, and newark airports.

예시로 나온 3개 중에 핵무기랑 비행기는 이해가 되는데 선과 토지에 관한 내용이 이해가 안되네요. 언어영역이 뛰어나신분 도와주세요.