diff --git a/Source/Modules/LangModelRelated/LMInstantiator.swift b/Source/Modules/LangModelRelated/LMInstantiator.swift
index 134aed54..96e6130d 100644
--- a/Source/Modules/LangModelRelated/LMInstantiator.swift
+++ b/Source/Modules/LangModelRelated/LMInstantiator.swift
@@ -31,8 +31,8 @@ import Foundation
 
 // 簡體中文模式與繁體中文模式共用全字庫擴展模組，故單獨處理。
 // 塞在 LMInstantiator 內的話，每個模式都會讀入一份全字庫，會多佔用 100MB 記憶體。
-private let lmCNS = vChewing.LMLite(consolidate: false)
-private let lmSymbols = vChewing.LMCore(reverse: true, consolidate: false, defaultScore: -13.0, forceDefaultScore: true)
+private var lmCNS = vChewing.LMLite(consolidate: false)
+private var lmSymbols = vChewing.LMCore(reverse: true, consolidate: false, defaultScore: -13.0, forceDefaultScore: true)
 
 extension vChewing {
   /// LMInstantiator is a facade for managing a set of models including
@@ -69,22 +69,21 @@ extension vChewing {
     /// 至於像全字庫這樣所有記錄都使用同一權重數值的模組，可以用 LMLite 以節省記憶體佔用。
     /// LMLite 的辭典內不會存儲權重資料，只會在每次讀取記錄時施加您給定的權重數值。
     /// LMLite 與 LMCore 都會用到多執行緒、以加速載入（不然的話，全部資料載入會耗費八秒左右）。
-    /// 然而，對於使用者語彙模型檔案而言，多執行緒可能會出現意料之外的問題，所以有了 LMLiteMono。
     /// LMReplacements 與 LMAssociates 均為特種模組，分別擔當語彙置換表資料與使用者聯想詞的資料承載工作。
 
     // 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)
+    var lmCore = LMCore(reverse: false, consolidate: false, defaultScore: -9.5, forceDefaultScore: false)
+    var lmMisc = LMCore(reverse: true, consolidate: false, defaultScore: -1, forceDefaultScore: false)
 
     // 聲明使用者語言模組。
     // 使用者語言模組使用多執行緒的話，可能會導致一些問題。有時間再仔細排查看看。
-    let lmUserPhrases = LMLiteMono(consolidate: true)
-    let lmFiltered = LMLiteMono(consolidate: true)
-    let lmUserSymbols = LMLiteMono(consolidate: true)
-    let lmReplacements = LMReplacments()
-    let lmAssociates = LMAssociates()
+    var lmUserPhrases = LMLite(consolidate: true)
+    var lmFiltered = LMLite(consolidate: true)
+    var lmUserSymbols = LMLite(consolidate: true)
+    var lmReplacements = LMReplacments()
+    var lmAssociates = LMAssociates()
 
     // 初期化的函數先保留
     override init() {}
diff --git a/Source/Modules/LangModelRelated/SubLMs/lmAssociates.swift b/Source/Modules/LangModelRelated/SubLMs/lmAssociates.swift
index 948c16f2..0fe67c9f 100644
--- a/Source/Modules/LangModelRelated/SubLMs/lmAssociates.swift
+++ b/Source/Modules/LangModelRelated/SubLMs/lmAssociates.swift
@@ -27,7 +27,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 import Foundation
 
 extension vChewing {
-  public class LMAssociates {
+  @frozen public struct LMAssociates {
     var keyValueMap: [String: [Megrez.KeyValuePair]] = [:]
     var theData: String = ""
 
@@ -36,17 +36,11 @@ extension vChewing {
       theData = ""
     }
 
-    deinit {
-      if isLoaded() {
-        close()
-      }
-    }
-
     public func isLoaded() -> Bool {
       !keyValueMap.isEmpty
     }
 
-    @discardableResult public func open(_ path: String) -> Bool {
+    @discardableResult mutating public func open(_ path: String) -> Bool {
       if isLoaded() {
         return false
       }
@@ -98,7 +92,7 @@ extension vChewing {
       return true
     }
 
-    public func close() {
+    mutating public func close() {
       if isLoaded() {
         keyValueMap.removeAll()
       }
diff --git a/Source/Modules/LangModelRelated/SubLMs/lmCore.swift b/Source/Modules/LangModelRelated/SubLMs/lmCore.swift
index ec666661..8ab55d5c 100644
--- a/Source/Modules/LangModelRelated/SubLMs/lmCore.swift
+++ b/Source/Modules/LangModelRelated/SubLMs/lmCore.swift
@@ -27,7 +27,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 import Foundation
 
 extension vChewing {
-  public class LMCore {
+  @frozen public struct LMCore {
     var keyValueScoreMap: [String: [Megrez.Unigram]] = [:]
     var theData: String = ""
     var shouldReverse: Bool = false
@@ -47,17 +47,11 @@ extension vChewing {
       shouldForceDefaultScore = forceDefaultScore
     }
 
-    deinit {
-      if isLoaded() {
-        close()
-      }
-    }
-
     public func isLoaded() -> Bool {
       !keyValueScoreMap.isEmpty
     }
 
-    @discardableResult public func open(_ path: String) -> Bool {
+    @discardableResult mutating public func open(_ path: String) -> Bool {
       if isLoaded() {
         return false
       }
@@ -132,7 +126,7 @@ extension vChewing {
       return true
     }
 
-    public func close() {
+    mutating public func close() {
       if isLoaded() {
         keyValueScoreMap.removeAll()
       }
@@ -152,17 +146,17 @@ extension vChewing {
       IME.prtDebugIntel(strDump)
     }
 
-    open func bigramsForKeys(precedingKey: String, key: String) -> [Megrez.Bigram] {
+    public func bigramsForKeys(precedingKey: String, key: String) -> [Megrez.Bigram] {
       // 這裡用了點廢話處理，不然函數構建體會被 Swift 格式整理工具給毀掉。
       // 其實只要一句「[Megrez.Bigram]()」就夠了。
       precedingKey == key ? [Megrez.Bigram]() : [Megrez.Bigram]()
     }
 
-    open func unigramsFor(key: String) -> [Megrez.Unigram] {
+    public func unigramsFor(key: String) -> [Megrez.Unigram] {
       keyValueScoreMap[key] ?? [Megrez.Unigram]()
     }
 
-    open func hasUnigramsFor(key: String) -> Bool {
+    public func hasUnigramsFor(key: String) -> Bool {
       keyValueScoreMap[key] != nil
     }
   }
diff --git a/Source/Modules/LangModelRelated/SubLMs/lmLite.swift b/Source/Modules/LangModelRelated/SubLMs/lmLite.swift
index a843474d..23156d93 100644
--- a/Source/Modules/LangModelRelated/SubLMs/lmLite.swift
+++ b/Source/Modules/LangModelRelated/SubLMs/lmLite.swift
@@ -27,7 +27,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 import Foundation
 
 extension vChewing {
-  public class LMLite {
+  @frozen public struct LMLite {
     var keyValueMap: [String: [Megrez.KeyValuePair]] = [:]
     var theData: String = ""
     var allowConsolidation = false
@@ -38,17 +38,11 @@ extension vChewing {
       allowConsolidation = consolidate
     }
 
-    deinit {
-      if isLoaded() {
-        close()
-      }
-    }
-
     public func isLoaded() -> Bool {
       !keyValueMap.isEmpty
     }
 
-    @discardableResult public func open(_ path: String) -> Bool {
+    @discardableResult mutating public func open(_ path: String) -> Bool {
       if isLoaded() {
         return false
       }
@@ -105,7 +99,7 @@ extension vChewing {
       return true
     }
 
-    public func close() {
+    mutating public func close() {
       if isLoaded() {
         keyValueMap.removeAll()
       }
diff --git a/Source/Modules/LangModelRelated/SubLMs/lmReplacements.swift b/Source/Modules/LangModelRelated/SubLMs/lmReplacements.swift
index b8e9b6ba..30337af6 100644
--- a/Source/Modules/LangModelRelated/SubLMs/lmReplacements.swift
+++ b/Source/Modules/LangModelRelated/SubLMs/lmReplacements.swift
@@ -27,7 +27,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 import Foundation
 
 extension vChewing {
-  public class LMReplacments {
+  @frozen public struct LMReplacments {
     var keyValueMap: [String: String] = [:]
     var theData: String = ""
 
@@ -36,17 +36,11 @@ extension vChewing {
       theData = ""
     }
 
-    deinit {
-      if isLoaded() {
-        close()
-      }
-    }
-
     public func isLoaded() -> Bool {
       !keyValueMap.isEmpty
     }
 
-    @discardableResult public func open(_ path: String) -> Bool {
+    @discardableResult mutating public func open(_ path: String) -> Bool {
       if isLoaded() {
         return false
       }
@@ -98,7 +92,7 @@ extension vChewing {
       return true
     }
 
-    public func close() {
+    mutating public func close() {
       if isLoaded() {
         keyValueMap.removeAll()
       }