diff --git a/src/menu/editor.js b/src/menu/editor.js
index 13bb9d6..3ab100a 100644
--- a/src/menu/editor.js
+++ b/src/menu/editor.js
@@ -15,6 +15,7 @@ import {
   createNotation,
   isNote,
   notations as N,
+  placeTie,
 } from "../util/notation";
 import {
   cloneParagraph,
@@ -179,6 +180,32 @@ const handleKeyPress = wrappedAction((ev) => {
         }
         break;
       }
+      case inputKey === "a" && !ctrl && !shift: {
+        if (!state.tieSourceKey) {
+          state.tieSourceKey = notation.key;
+        } else if (state.tieSourceKey === notation.key) {
+          state.tieSourceKey = null;
+        } else {
+          placeTie(notation);
+        }
+        break;
+      }
+      case inputKey === "a" && !ctrl && shift: {
+        if (notation.tieTo) {
+          const { notation: tieDesc } = findParagraphAndNotation(
+            notation.tieTo
+          );
+          if (tieDesc) {
+            tieDesc.tieTo = null;
+          }
+          notation.tieTo = null;
+          break;
+        }
+      }
+      case inputKey === "!" && !ctrl: {
+        notation.breakUnderline = !notation.breakUnderline;
+        break;
+      }
       case inputKey === "~" && !ctrl: {
         if (notation.topDecorators.includes("~")) {
           notation.topDecorators.splice(notation.topDecorators.indexOf("~"), 1);
diff --git a/src/view/HelpModal/index.js b/src/view/HelpModal/index.js
index 5490cd2..9430d9a 100644
--- a/src/view/HelpModal/index.js
+++ b/src/view/HelpModal/index.js
@@ -44,14 +44,17 @@ function HelpModal({ visible, onVisibleChange }) {
       直接按键盘上相应的键即可输入到当前符号。支持的音符符号有：
       <p>
         <kbd className={Styles.kbd}>0~7</kbd>
-        <kbd className={Styles.kbd}>( )</kbd>
+        <kbd className={Styles.kbd}>─ ( )</kbd>
       </p>
       <h4>输入辅助元素</h4>
       <ul className={Styles.list}>
+        <KeyboardDescItem kbd="a" desc="选择连音线起止符号" />
+        <KeyboardDescItem kbd="A" desc="删除连音线" />
         <KeyboardDescItem kbd="|" desc="输入小节线" />
         <KeyboardDescItem kbd="." desc="输入附点" />
         <KeyboardDescItem kbd="~" desc="颤音符号" />
-        <KeyboardDescItem kbd="u / U" desc="增减时线" />
+        <KeyboardDescItem kbd="u / U" desc="增减增减时线" />
+        <KeyboardDescItem kbd="!" desc="打断增减时线" />
         <KeyboardDescItem kbd="8 / *" desc="八度圆点" />
         <KeyboardDescItem kbd="# / b" desc="音符升/降" />
       </ul>