应该是some...others，some...the others，one...the other.
some...others... 一些…一些… （指复数名词把整体分为若干份，some...others...所陈述的只是其中的两部分）
some...the others，一些…另一些…（指复数名词，把整体分就为两份，所陈述的也就是这两部分）
one...the other 一个……另一个………（所陈述的是“两个”可数名词单数。）
there are many students on the playground,some are reading books , some are playing badminton,others are having a walk. (可能还有人在打乒乓球，还有人在坐着聊天……)
there are 50 students in our class, some are from Beijing , the others are from shanghai.(这50名学生只来自北京上海，没有别的地方的学生了)
I have two sons, one is a doctor, and the other (one )is a teacher.
参考资料：自己总结