diff --git a/Source/Modules/LangModelRelated/SubLMs/lmReplacements.swift b/Source/Modules/LangModelRelated/SubLMs/lmReplacements.swift
new file mode 100644
index 00000000..d18c21eb
--- /dev/null
+++ b/Source/Modules/LangModelRelated/SubLMs/lmReplacements.swift
@@ -0,0 +1,115 @@
+// Copyright (c) 2021 and onwards The vChewing Project (MIT-NTL License).
+// Refactored from the ObjCpp-version of this class by:
+// (c) 2011 and onwards The OpenVanilla Project (MIT License).
+/*
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+1. The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+2. No trademark license is granted to use the trade names, trademarks, service
+marks, or product names of Contributor, except as required to fulfill notice
+requirements above.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+import Foundation
+
+extension vChewing {
+	public class LMReplacments {
+		var keyValueMap: [String: String] = [:]
+		var theData: String = ""
+
+		public init() {
+			keyValueMap = [:]
+			theData = ""
+		}
+
+		deinit {
+			if isLoaded() {
+				close()
+			}
+		}
+
+		public func isLoaded() -> Bool {
+			!keyValueMap.isEmpty
+		}
+
+		@discardableResult public func open(_ path: String) -> Bool {
+			if isLoaded() {
+				return false
+			}
+
+			if !LMConsolidator.fixEOF(path: path) {
+				return false
+			}
+			if !LMConsolidator.consolidate(path: path, pragma: true) {
+				return false
+			}
+
+			do {
+				theData = try String(contentsOfFile: path, encoding: .utf8)
+			} catch {
+				IME.prtDebugIntel("\(error)")
+				IME.prtDebugIntel("↑ Exception happened when reading Associated Phrases data.")
+				return false
+			}
+
+			let length = theData.count
+			guard length > 0 else {
+				return false
+			}
+
+			let arrData = theData.components(separatedBy: "\n")
+			for (lineID, lineContent) in arrData.enumerated() {
+				if !lineContent.hasPrefix("#") {
+					if lineContent.components(separatedBy: " ").count < 2 {
+						if arrData.last != "" {
+							IME.prtDebugIntel("Line #\(lineID + 1) Wrecked: \(lineContent)")
+						}
+						continue
+					}
+					var currentKV = KeyValue()
+					for (unitID, unitContent) in lineContent.components(separatedBy: " ").enumerated() {
+						switch unitID {
+							case 0:
+								currentKV.key = unitContent
+							case 1:
+								currentKV.value = unitContent
+							default: break
+						}
+					}
+					keyValueMap[currentKV.key] = currentKV.value
+				}
+			}
+			IME.prtDebugIntel("\(keyValueMap.count) entries of data loaded from: \(path)")
+			theData = ""
+			return true
+		}
+
+		public func close() {
+			if isLoaded() {
+				keyValueMap.removeAll()
+			}
+		}
+
+		public func valuesFor(key: String) -> String {
+			var v = ""
+			if let matched = keyValueMap[key] {
+				v = matched
+			}
+			return v
+		}
+	}
+}