range.swift

if let range0 = text.range(of: "다라") {
    let startWord = text[range0].startIndex
    let endWord = text[range0].endIndex
    let w0 = text[text.startIndex ..< startWord]
    let w1 = text[startWord ..< endWord]
    let w2 = text[endWord ..< text.endIndex]
    print("\(w0)\n\(w1)\n\(w2)")
}