diff --git a/Source/Modules/LangModelRelated/LMInstantiator.swift b/Source/Modules/LangModelRelated/LMInstantiator.swift
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+// 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.
+*/
+
+// NOTE: We still keep some of the comments left by Zonble,
+// regardless that he is not in charge of this Swift module。
+
+import Foundation
+
+extension vChewing {
+	/// LMInstantiator is a facade for managing a set of models including
+	/// the input method language model, user phrases and excluded phrases.
+	///
+	/// It is the primary model class that the input controller and grammar builder
+	/// of vChewing talks to. When the grammar builder starts to build a sentence
+	/// from a series of BPMF readings, it passes the readings to the model to see
+	/// if there are valid unigrams, and use returned unigrams to produce the final
+	/// results.
+	///
+	/// LMInstantiator combine and transform the unigrams from the primary language
+	/// model and user phrases. The process is
+	///
+	/// 1) Get the original unigrams.
+	/// 2) Drop the unigrams whose value is contained in the exclusion map.
+	/// 3) Replace the values of the unigrams using the phrase replacement map.
+	/// 4) Replace the values of the unigrams using an external converter lambda.
+	/// 5) Drop the duplicated phrases.
+	///
+	/// The controller can ask the model to load the primary input method language
+	/// model while launching and to load the user phrases anytime if the custom
+	/// files are modified. It does not keep the reference of the data pathes but
+	/// you have to pass the paths when you ask it to do loading.
+	public class LMInstantiator: Megrez.LanguageModel {
+		// 在函數內部用以記錄狀態的開關。
+		public var isPhraseReplacementEnabled = false
+		public var isCNSEnabled = false
+		public var isSymbolEnabled = false
+
+		// 聲明原廠語言模組
+		/// Reverse 的話，第一欄是注音，第二欄是對應的漢字，第三欄是可能的權重。
+		/// 不 Reverse 的話，第一欄是漢字，第二欄是對應的注音，第三欄是可能的權重。
+		let lmCore = LMCore(reverse: false, consolidate: false, defaultScore: -9.5, forceDefaultScore: false)
+		let lmMisc = LMCore(reverse: true, consolidate: false, defaultScore: -1, forceDefaultScore: false)
+		let lmSymbols = LMLite(defaultScore: -13.0, consolidate: true)
+		let lmCNS = LMLite(defaultScore: -11.0, consolidate: true)
+
+		// 聲明使用者語言模組
+		let lmUserPhrases = LMLite(defaultScore: 0.0, consolidate: true)
+		let lmFiltered = LMLite(defaultScore: 0.0, consolidate: true)
+		let lmUserSymbols = LMLite(defaultScore: -12.0, consolidate: true)
+		let lmReplacements = LMReplacments()
+		let lmAssociates = LMAssociates()
+
+		// 初期化的函數先保留
+		override init() {}
+
+		// 自我析構前要關掉全部的語言模組
+		deinit {
+			lmCore.close()
+			lmMisc.close()
+			lmSymbols.close()
+			lmCNS.close()
+			lmUserPhrases.close()
+			lmFiltered.close()
+			lmUserSymbols.close()
+			lmReplacements.close()
+			lmAssociates.close()
+		}
+
+		// 以下這些函數命名暫時保持原樣，等弒神行動徹底結束了再調整。
+
+		public func isDataModelLoaded() -> Bool { lmCore.isLoaded() }
+		public func loadLanguageModel(path: String) {
+			if FileManager.default.isReadableFile(atPath: path) {
+				lmCore.close()
+				lmCore.open(path)
+			}
+		}
+
+		public func isCNSDataLoaded() -> Bool { lmCNS.isLoaded() }
+		public func loadCNSData(path: String) {
+			if FileManager.default.isReadableFile(atPath: path) {
+				lmCNS.close()
+				lmCNS.open(path)
+			}
+		}
+
+		public func isMiscDataLoaded() -> Bool { lmMisc.isLoaded() }
+		public func loadMiscData(path: String) {
+			if FileManager.default.isReadableFile(atPath: path) {
+				lmMisc.close()
+				lmMisc.open(path)
+			}
+		}
+
+		public func isSymbolDataLoaded() -> Bool { lmSymbols.isLoaded() }
+		public func loadSymbolData(path: String) {
+			if FileManager.default.isReadableFile(atPath: path) {
+				lmSymbols.close()
+				lmSymbols.open(path)
+			}
+		}
+
+		public func loadUserPhrases(path: String, filterPath: String) {
+			if FileManager.default.isReadableFile(atPath: path) {
+				lmUserPhrases.close()
+				lmUserPhrases.open(path)
+			}
+			if FileManager.default.isReadableFile(atPath: filterPath) {
+				lmFiltered.close()
+				lmFiltered.open(filterPath)
+			}
+		}
+
+		public func loadUserSymbolData(path: String) {
+			if FileManager.default.isReadableFile(atPath: path) {
+				lmUserSymbols.close()
+				lmUserSymbols.open(path)
+			}
+		}
+
+		public func loadUserAssociatedPhrases(path: String) {
+			if FileManager.default.isReadableFile(atPath: path) {
+				lmAssociates.close()
+				lmAssociates.open(path)
+			}
+		}
+
+		public func loadPhraseReplacementMap(path: String) {
+			if FileManager.default.isReadableFile(atPath: path) {
+				lmReplacements.close()
+				lmReplacements.open(path)
+			}
+		}
+
+		// MARK: - Core Functions (Public)
+
+		/// Not implemented since we do not have data to provide bigram function.
+		// public func bigramsForKeys(preceedingKey: String, key: String) -> [Megrez.Bigram] { }
+
+		/// Returns a list of available unigram for the given key.
+		/// @param key:String represents the BPMF reading or a symbol key.
+		/// For instance, it you pass "ㄉㄨㄟˇ", it returns "㨃" and other possible candidates.
+		override open func unigramsFor(key: String) -> [Megrez.Unigram] {
+			if key == " " {
+				/// 給空格鍵指定輸出值。
+				let spaceUnigram = Megrez.Unigram(
+					keyValue: Megrez.KeyValuePair(key: " ", value: " "),
+					score: 0
+				)
+				return [spaceUnigram]
+			}
+
+			/// 準備不同的語言模組容器。
+			var coreUnigrams: [Megrez.Unigram] = []
+			var miscUnigrams: [Megrez.Unigram] = []
+			var symbolUnigrams: [Megrez.Unigram] = []
+			var userUnigrams: [Megrez.Unigram] = []
+			var userSymbolUnigrams: [Megrez.Unigram] = []
+			var cnsUnigrams: [Megrez.Unigram] = []
+
+			var insertedPairs: Set<Megrez.KeyValuePair> = []  // 具體用途有待商榷
+			var filteredPairs: Set<Megrez.KeyValuePair> = []
+
+			// 開始逐漸往容器陣列內塞入資料
+			let filteredUnigrams: [Megrez.Unigram] =
+				lmFiltered.hasUnigramsFor(key: key) ? lmFiltered.unigramsFor(key: key) : []
+			for unigram in filteredUnigrams {
+				filteredPairs.insert(unigram.keyValue)
+			}
+
+			if lmUserPhrases.hasUnigramsFor(key: key) {
+				var rawUserUnigrams: [Megrez.Unigram] = []
+				// 用 reversed 指令讓使用者語彙檔案內的詞條優先順序隨著行數增加而逐漸增高。
+				// 這樣一來就可以在就地新增語彙時徹底複寫優先權。
+				// 將兩句差分也是為了讓 rawUserUnigrams 的類型不受可能的影響。
+				rawUserUnigrams.append(contentsOf: lmUserPhrases.unigramsFor(key: key).reversed())
+				userUnigrams = filterAndTransform(
+					unigrams: rawUserUnigrams, filter: filteredPairs, inserted: &insertedPairs
+				)
+			}
+
+			if lmUserPhrases.hasUnigramsFor(key: key) {
+				let rawUserUnigrams: [Megrez.Unigram] = lmUserPhrases.unigramsFor(key: key)
+				userUnigrams = filterAndTransform(
+					unigrams: rawUserUnigrams, filter: filteredPairs, inserted: &insertedPairs
+				)
+			}
+
+			if lmMisc.hasUnigramsFor(key: key) {
+				let rawMiscUnigrams: [Megrez.Unigram] = lmMisc.unigramsFor(key: key)
+				miscUnigrams = filterAndTransform(
+					unigrams: rawMiscUnigrams, filter: filteredPairs, inserted: &insertedPairs
+				)
+			}
+
+			if lmCore.hasUnigramsFor(key: key) {
+				let rawCoreUnigrams: [Megrez.Unigram] = lmCore.unigramsFor(key: key)
+				coreUnigrams = filterAndTransform(
+					unigrams: rawCoreUnigrams, filter: filteredPairs, inserted: &insertedPairs
+				)
+			}
+
+			if isSymbolEnabled {
+				if lmUserSymbols.hasUnigramsFor(key: key) {
+					let rawUserSymbolUnigrams: [Megrez.Unigram] = lmUserSymbols.unigramsFor(key: key)
+					userSymbolUnigrams = filterAndTransform(
+						unigrams: rawUserSymbolUnigrams, filter: filteredPairs, inserted: &insertedPairs
+					)
+				} else {
+					IME.prtDebugIntel("Not found in UserSymbolUnigram: \(key)")
+				}
+
+				if lmSymbols.hasUnigramsFor(key: key) {
+					let rawSymbolUnigrams: [Megrez.Unigram] = lmSymbols.unigramsFor(key: key)
+					symbolUnigrams = filterAndTransform(
+						unigrams: rawSymbolUnigrams, filter: filteredPairs, inserted: &insertedPairs
+					)
+				} else {
+					IME.prtDebugIntel("Not found in UserUnigram: \(key)")
+				}
+			}
+
+			if lmCNS.hasUnigramsFor(key: key), isCNSEnabled {
+				let rawCNSUnigrams: [Megrez.Unigram] = lmCNS.unigramsFor(key: key)
+				cnsUnigrams = filterAndTransform(
+					unigrams: rawCNSUnigrams, filter: filteredPairs, inserted: &insertedPairs
+				)
+			}
+
+			let allUnigrams: [Megrez.Unigram] =
+				userUnigrams + miscUnigrams + coreUnigrams + cnsUnigrams + userSymbolUnigrams + symbolUnigrams
+
+			return allUnigrams
+		}
+
+		/// If the model has unigrams for the given key.
+		/// @param key The key.
+		override open func hasUnigramsFor(key: String) -> Bool {
+			if key == " " { return true }
+
+			if !lmFiltered.hasUnigramsFor(key: key) {
+				return lmUserPhrases.hasUnigramsFor(key: key) || lmCore.hasUnigramsFor(key: key)
+			}
+
+			return !unigramsFor(key: key).isEmpty
+		}
+
+		public func associatedPhrasesForKey(_ key: String) -> [String] {
+			lmAssociates.valuesFor(key: key) ?? []
+		}
+
+		public func hasAssociatedPhrasesForKey(_ key: String) -> Bool {
+			lmAssociates.hasValuesFor(key: key)
+		}
+
+		// MARK: - Core Functions (Private)
+
+		func filterAndTransform(
+			unigrams: [Megrez.Unigram],
+			filter filteredPairs: Set<Megrez.KeyValuePair>,
+			inserted insertedPairs: inout Set<Megrez.KeyValuePair>
+		) -> [Megrez.Unigram] {
+			var results: [Megrez.Unigram] = []
+
+			for unigram in unigrams {
+				let pairToDealWith: Megrez.KeyValuePair = unigram.keyValue
+				if filteredPairs.contains(pairToDealWith) {
+					continue
+				}
+
+				var pair: Megrez.KeyValuePair = pairToDealWith
+				if isPhraseReplacementEnabled {
+					let replacement = lmReplacements.valuesFor(key: pair.key)
+					if !replacement.isEmpty {
+						IME.prtDebugIntel(replacement)
+						pair.value = replacement
+					}
+				}
+
+				if !insertedPairs.contains(pair) {
+					results.append(Megrez.Unigram(keyValue: pair, score: unigram.score))
+					insertedPairs.insert(pair)
+				}
+			}
+			return results
+		}
+	}
+}