re-

re-

Words formed with the prefix re- are generally unhyphened (rearrange, regroup, reopen, reuse, etc.) except when the second element begins with an e (re-enter, re-evaluation, etc.) or when the combination needs to be distinguished from another word with the same spelling, e.g. re-collect = collect again (recollect = to remember) and re-sign = sign again (resign = give up one's job). Other words in this last category include re-count, re-cover, re-creation, re-form (and re-formation), re-serve, re-soluble, re-solve, re-sort.