Between 還是 among 呢？

Between 和 among 都是介系詞。Between 意為「在 (兩個或兩個以上的人事物) 之間」，而這兩者有明確的分開或區別。Among 意為「在 (三個或三個以上的人事物) 之中；為…所圍繞」，而這三者並沒有明確的分開或區別，因為他們是屬於同一群體的一部份。例如：

Trade between Taiwan and Thailand has increased sharply in the past year. (在過去一年間，台灣和泰國之間的貿易急劇增加)
There is a fence between the two gardens. (兩個花園之間有一道柵欄)
Peter saw a few familiar faces among the crowd. (彼得在人群中看見了幾張熟悉的面孔)

Between 後面最常接兩個單數或複數名詞片語 (noun phrases)，而這兩個名詞片語之間用 and 連接起來，即 between NP1 and NP2。例如：

The negotiations between the union and management have reached a significant agreement. (工會和資方的談判已達成重大協議)
What’s the difference between cheetahs and leopards? (獵豹和花豹有何不同呢？)

Between 亦可接表示兩個人事物的名詞或代名詞。例如：

There is a significant difference in memory between these two computers. (這兩部電腦在記憶體方面有顯著的差別)
They agreed to split the profits between (the two of) them on a fifty-fifty basis. (他們同意將利潤對分)

介於兩個時間或任意兩個數字之間只能使用 between A and B (A 和 B 在此為兩個不同的時間或數字)，不能使用 among；換言之，between A and B 為固定搭配，與 from A to B 同義。例如：

I was watching TV between 7.00 pm and 7.30 pm yesterday. (昨天下午七時至七時半我正在看電視) (正)
= I was watching TV from 7.00 pm to 7.30 pm yesterday. (正)
I was watching TV among 7.00 pm and 7.30 pm yesterday. (誤)
These novels were written between 2010 and 2018. (這些小說寫於 2010 至 2018 年間) (正)
These novels were written among 2010 and 2018. (誤)
That fishing village is between 30 and 50 kilometers away. (那個漁村距離這裡約 30 到 50 公里) (正)
That fishing village is among 30 and 50 kilometers away. (誤)
His three children are between the ages of 9 and 13. (他的三個小孩年齡介於 9 歲和 13 歲之間) (正)
His three children are among the ages of 9 and 13. (誤)

Between 最常位在 connection、difference、distinction、link 和 relationship 等名詞以及 choose、differentiate、distinguish 和 divide 等動詞之後。例如：

There’s a strong connection/relationship between lung cancer and smoking. (肺癌和吸菸之間有強烈的關連)
There’s a clear difference/distinction between the lifestyles in the two regions. (這兩個地區的生活方式有著明顯的不同)
John had to choose between the two women in his life. (面對生命中的兩個女人，約翰必須從中作出選擇)
It’s important to distinguish between poisonous and edible mushrooms. (分清楚有毒蘑菇和可食用蘑菇至關重要)

根據上述，among 係用來表示「在 (三個或三個以上的人事物) 之中；為…所圍繞」的意思，其後通常接複數名詞片語。例如：

在相當常見的 among others 和 among other things 這兩個同義片語中，among 意為「除…之外還；也」(as well as, in addition to)，亦即 among 後面的人事物包含在內。例如：

Mary has worked as an estate agent among others. (除了其他工作，瑪麗現在也做房屋仲介) －亦即瑪麗做了很多工作，房屋仲介是其中之一。
Jack, among other things (= as well as other things), talked about the 2020 presidential election. (除了別的事情，傑克還談到 2020 總統選舉)

最後要提的是，amongst 有時會被用來替代 among，兩者的意思和用法皆同，但 amongst 比較正式且比較少見。例如：