diff --git a/Packages/vChewing_Shared/Sources/Shared/Protocols/CtlCandidateProtocol.swift b/Packages/vChewing_Shared/Sources/Shared/Protocols/CtlCandidateProtocol.swift
index ec9df4c8..67f5cc3d 100644
--- a/Packages/vChewing_Shared/Sources/Shared/Protocols/CtlCandidateProtocol.swift
+++ b/Packages/vChewing_Shared/Sources/Shared/Protocols/CtlCandidateProtocol.swift
@@ -10,10 +10,8 @@ import Cocoa
 
 public protocol CtlCandidateDelegate: AnyObject {
   func candidatePairs(conv: Bool) -> [(String, String)]
-  func candidatePairAt(_ index: Int) -> (String, String)
   func candidatePairSelected(at index: Int)
   func candidates(_ sender: Any!) -> [Any]!
-  func buzz()
   var selectionKeys: String { get }
 }
 
diff --git a/Source/Modules/SessionCtl_Delegates.swift b/Source/Modules/SessionCtl_Delegates.swift
index d992c1ea..1f3842fb 100644
--- a/Source/Modules/SessionCtl_Delegates.swift
+++ b/Source/Modules/SessionCtl_Delegates.swift
@@ -57,10 +57,6 @@ extension SessionCtl: CtlCandidateDelegate {
     PrefMgr.shared.useIMKCandidateWindow ? "123456789" : PrefMgr.shared.candidateKeys
   }
 
-  func buzz() {
-    IMEApp.buzz()
-  }
-
   func candidatePairs(conv: Bool = false) -> [(String, String)] {
     if !state.isCandidateContainer || state.candidates.isEmpty { return [] }
     if !conv || PrefMgr.shared.cns11643Enabled || state.candidates[0].0.contains("_punctuation") {
@@ -75,13 +71,6 @@ extension SessionCtl: CtlCandidateDelegate {
     return convertedCandidates
   }
 
-  func candidatePairAt(_ index: Int) -> (String, String) {
-    if state.isCandidateContainer, state.candidates.count > index {
-      return state.candidates[index]
-    }
-    return ("", "")
-  }
-
   func candidatePairSelected(at index: Int) {
     if state.type == .ofSymbolTable, (0..<state.node.members.count).contains(index) {
       let node = state.node.members[index]