Make new friends, but keep the old.
One is silver, and the other gold.
(A Korean middle school English textbook)
Does one indicate new friends or any of both: new friends or the old ones?
It refers to new friends. You have “new friends” and “old friends” mentioned earlier, and then “one” and “the other” referring respectively to the first (new friends) and the second (old friends).
Source : Link , Question Author : Listenever , Answer Author : fluffy