diff --git a/Packages/vChewing_MainAssembly/Sources/MainAssembly/LMMgr_UserPhraseStructure.swift b/Packages/vChewing_MainAssembly/Sources/MainAssembly/LMMgr_UserPhraseStructure.swift
index 9e76e309..6b2937f7 100644
--- a/Packages/vChewing_MainAssembly/Sources/MainAssembly/LMMgr_UserPhraseStructure.swift
+++ b/Packages/vChewing_MainAssembly/Sources/MainAssembly/LMMgr_UserPhraseStructure.swift
@@ -67,8 +67,24 @@ public extension LMMgr {
     }
 
     public func write(toFilter: Bool) -> Bool {
-      guard isValid, LMMgr.chkUserLMFilesExist(inputMode) else { return false }
-
+      guard isValid else {
+        vCLog("UserPhrase.write(toFilter: \(toFilter.description)) Error: UserPhrase invalid.")
+        return false
+      }
+      guard LMMgr.chkUserLMFilesExist(inputMode) else {
+        vCLog("UserPhrase.write(toFilter: \(toFilter.description)) Error: UserLMFiles not exist.")
+        return false
+      }
+      if !toFilter, isAlreadyFiltered {
+        vCLog("START REMOVING THIS PHRASE FROM FILTER.")
+        removeFromFilter()
+        // 在整理過一遍之後，如果還是被排除的狀態的話，則證明語彙濾除清單檔案有格式問題、需要整理。
+        // 這種情況下，先強制整理，再排除。
+        if isAlreadyFiltered {
+          removeFromFilter(forceConsolidate: true)
+        }
+        return !isAlreadyFiltered
+      }
       /// 施工筆記：
       /// 有些使用者的語彙檔案已經過於龐大了（超過一千行），
       /// 每次寫入時都全文整理格式的話，會引發嚴重的效能問題。
@@ -80,11 +96,21 @@ public extension LMMgr {
         let dict = try FileManager.default.attributesOfItem(atPath: theURL.path)
         if let value = dict[FileAttributeKey.size] as? UInt64 { fileSize = value }
       } catch {
+        vCLog("UserPhrase.write(toFilter: \(toFilter.description)) Error: Target file size is null.")
+        return false
+      }
+      guard let fileSize = fileSize else {
+        vCLog("UserPhrase.write(toFilter: \(toFilter.description)) Error: Target file size is null.")
+        return false
+      }
+      guard var dataToInsert = "\(description)\n".data(using: .utf8) else {
+        vCLog("UserPhrase.write(toFilter: \(toFilter.description)) Error: Failed from preparing insertion data.")
+        return false
+      }
+      guard let writeFile = FileHandle(forUpdatingAtPath: theURL.path) else {
+        vCLog("UserPhrase.write(toFilter: \(toFilter.description)) Error: Failed from initiating file handle.")
         return false
       }
-      guard let fileSize = fileSize else { return false }
-      guard var dataToInsert = "\(description)\n".data(using: .utf8) else { return false }
-      guard let writeFile = FileHandle(forUpdatingAtPath: theURL.path) else { return false }
       defer { writeFile.closeFile() }
       if fileSize > 0 {
         writeFile.seek(toFileOffset: fileSize - 1)
@@ -96,5 +122,71 @@ public extension LMMgr {
       writeFile.write(dataToInsert)
       return true
     }
+
+    /// 嘗試將該筆記錄從語彙濾除清單檔案內移除，但可能會因為語彙濾除清單檔案尚未整理的格式而失敗。
+    ///
+    /// 原理：發現該當條目時，直接全部置換為 NULL（0x0）。這樣可以最小化磁碟寫入次數。
+    /// （不然還得將當前位置後面的內容整個重新寫入。）
+    /// - Parameter confirm: 再檢查一遍是否符合執行條件。不符合的話，就啥也不做。
+    @discardableResult public func removeFromFilter(confirm: Bool = false, forceConsolidate: Bool = false) -> Bool {
+      let debugOutput = NSMutableString()
+      defer {
+        if debugOutput.length > 0 { vCLog(debugOutput.description) }
+      }
+      if confirm {
+        guard isValid else {
+          debugOutput.append("removeFromFilter(): This user phrase pair is invalid. \(descriptionCells.prefix(2).joined(separator: " "))")
+          return false
+        }
+        guard isAlreadyFiltered else {
+          debugOutput.append("removeFromFilter(): This user phrase pair is not in the filtered list.")
+          return false
+        }
+      }
+      let theURL = LMMgr.userDictDataURL(mode: inputMode, type: .theFilter)
+      if forceConsolidate, !vChewingLM.LMConsolidator.consolidate(path: theURL.path, pragma: false) { return false }
+      // Get FileSize.
+      var fileSize: UInt64?
+      do {
+        let dict = try FileManager.default.attributesOfItem(atPath: theURL.path)
+        if let value = dict[FileAttributeKey.size] as? UInt64 { fileSize = value }
+      } catch {
+        debugOutput.append("removeFromFilter(): Failed from getting the file size of the filter list file.")
+        return false
+      }
+      guard let fileSize = fileSize else { return false }
+      // Prepare FileHandle.
+      guard let fileHandle = FileHandle(forUpdatingAtPath: theURL.path) else {
+        debugOutput.append("removeFromFilter(): Failed from handling the filter list file.")
+        return false
+      }
+      defer { fileHandle.closeFile() }
+      // Get bytes for matching.
+      let usefulCells = descriptionCells.prefix(2)
+      guard usefulCells.count == 2 else { return false }
+      guard let data1 = usefulCells.joined(separator: " ").data(using: .utf8) else { return false }
+      guard let data2 = usefulCells.joined(separator: "\t").data(using: .utf8) else { return false }
+      let bufferLength = data1.count // data1 與 data2 長度相等
+      guard fileSize >= bufferLength else { return true }
+      let blankData = Data([UInt8](repeating: 0x0, count: bufferLength)) // 用來搞填充的垃圾資料
+      let sharpData = Data([0x23]) // Sharp Sign (#)
+      fileHandle.seek(toFileOffset: 0) // 從頭開始讀取處理。
+      for currentOffset in -1 ..< (Int(fileSize) - bufferLength - 1) {
+        /// !! 注意：FileHandle 的 seek 位置會在每次 readData() / write() 之後都有變動。
+        // 確定手術位置
+        let currentWorkingOffset = UInt64(currentOffset + 1)
+        // 讀取且檢查當前位元組
+        fileHandle.seek(toFileOffset: UInt64(max(0, currentOffset)))
+        let currentByte = fileHandle.readData(ofLength: 1)
+        guard currentByte != sharpData else { continue }
+        // 開始手術
+        fileHandle.seek(toFileOffset: currentWorkingOffset)
+        let dataScoped = fileHandle.readData(ofLength: bufferLength)
+        guard [data1, data2].contains(dataScoped) else { continue }
+        fileHandle.seek(toFileOffset: currentWorkingOffset)
+        fileHandle.write(blankData)
+      }
+      return true
+    }
   }
 }