diff --git a/src/muya/lib/contentState/backspaceCtrl.js b/src/muya/lib/contentState/backspaceCtrl.js
index bd351e7e..d65b195c 100644
--- a/src/muya/lib/contentState/backspaceCtrl.js
+++ b/src/muya/lib/contentState/backspaceCtrl.js
@@ -147,8 +147,7 @@ const backspaceCtrl = ContentState => {
       }
       return this.partialRender()
     }
-    // fix: #67 problem 1
-    if (startBlock.icon) return event.preventDefault()
+
     // fix: unexpect remove all editor html. #67 problem 4
     if (startBlock.type === 'figure' && !startBlock.preSibling) {
       event.preventDefault()
@@ -171,12 +170,8 @@ const backspaceCtrl = ContentState => {
       return this.render()
     }
 
-    if (startBlock.functionType === 'languageInput' && start.offset === 0) {
-      return event.preventDefault()
-    }
-
     // If select multiple paragraph or multiple characters in one paragraph, just let
-    // updateCtrl to handle this case.
+    // inputCtrl to handle this case.
     if (start.key !== end.key || start.offset !== end.offset) {
       return
     }
diff --git a/src/muya/lib/contentState/inputCtrl.js b/src/muya/lib/contentState/inputCtrl.js
index 5f9d0e7c..5dda1d97 100644
--- a/src/muya/lib/contentState/inputCtrl.js
+++ b/src/muya/lib/contentState/inputCtrl.js
@@ -82,6 +82,7 @@ const inputCtrl = ContentState => {
     if (!start || !end) {
       return
     }
+
     const { start: oldStart, end: oldEnd } = this.cursor
     const key = start.key
     const block = this.getBlock(key)
@@ -92,9 +93,20 @@ const inputCtrl = ContentState => {
 
     if (oldStart.key !== oldEnd.key) {
       const startBlock = this.getBlock(oldStart.key)
+      const startOutmostBlock = this.findOutMostBlock(startBlock)
       const endBlock = this.getBlock(oldEnd.key)
-
-      this.removeBlocks(startBlock, endBlock)
+      const endOutmostBlock = this.findOutMostBlock(endBlock)
+      if (
+        // fix #918.
+        startBlock.functionType === 'languageInput' &&
+        startOutmostBlock === endOutmostBlock &&
+        !endBlock.nextSibling
+      ) {
+        this.removeBlocks(startBlock, endBlock, false)
+        endBlock.text = ''
+      } else {
+        this.removeBlocks(startBlock, endBlock)
+      }
       if (this.blocks.length === 1) {
         needRenderAll = true
       }
diff --git a/src/muya/lib/selection/index.js b/src/muya/lib/selection/index.js
index c54ee426..7f1d6a2a 100644
--- a/src/muya/lib/selection/index.js
+++ b/src/muya/lib/selection/index.js
@@ -439,9 +439,43 @@ class Selection {
 
   getCursorRange () {
     let { anchorNode, anchorOffset, focusNode, focusOffset } = this.doc.getSelection()
+    // when the first paragraph is task list, press ctrl + a, then press backspace will cause bug
+    // use code bellow to fix the bug
+    const findFirstTextNode = anchor => {
+      if (anchor.nodeType === 3) return anchor
+      // if it's a empty line, just return the span element.
+      if (
+        anchor.nodeType === 1 &&
+        anchor.nodeName === 'SPAN' &&
+        anchor.textContent === '' &&
+        anchor.classList.contains('ag-line')
+      ) {
+        return anchor
+      }
+      const children = anchor.childNodes
+      for (const node of children) {
+        if (
+          /input/i.test(node.nodeName) ||
+          node.nodeType === 1 && node.getAttribute('contenteditable') === 'false'
+        ) {
+          continue
+        }
+        return findFirstTextNode(node)
+      }
+    }
+    let needFix = false
+    if (anchorNode.nodeName === 'LI') {
+      needFix = true
+      anchorNode = findFirstTextNode(anchorNode)
+    }
+
+    if (focusNode.nodeName === 'LI') {
+      needFix = true
+      focusNode = findFirstTextNode(focusNode)
+    }
+
     let startParagraph = findNearestParagraph(anchorNode)
     let endParagraph = findNearestParagraph(focusNode)
-
     if (!startParagraph || !endParagraph) {
       return {
         start: null,
@@ -449,21 +483,6 @@ class Selection {
       }
     }
 
-    // when the first paragraph is task list, press ctrl + a, then press backspace will cause bug
-    // use code bellow to fix the bug
-    const findFirstTextNode = anchor => {
-      if (anchor.nodeType === 3) return anchor
-      const children = anchor.childNodes
-      for (const node of children) {
-        if (node.nodeName !== 'INPUT') {
-          return findFirstTextNode(node)
-        }
-      }
-    }
-    if (anchorNode.nodeName === 'LI') {
-      anchorNode = findFirstTextNode(anchorNode)
-    }
-
     const getOffsetOfParagraph = (node, paragraph) => {
       let offset = 0
       let preSibling = node
@@ -481,11 +500,13 @@ class Selection {
         : offset + getOffsetOfParagraph(node.parentNode, paragraph)
     }
 
+    let result = null
+
     if (startParagraph === endParagraph) {
       const key = startParagraph.id
       const offset1 = getOffsetOfParagraph(anchorNode, startParagraph) + anchorOffset
       const offset2 = getOffsetOfParagraph(focusNode, endParagraph) + focusOffset
-      return {
+      result = {
         start: { key, offset: Math.min(offset1, offset2) },
         end: { key, offset: Math.max(offset1, offset2) }
       }
@@ -503,11 +524,15 @@ class Selection {
         }
       }
       if (order) {
-        return rawCursor
+        result = rawCursor
       } else {
-        return { start: rawCursor.end, end: rawCursor.start }
+        result = { start: rawCursor.end, end: rawCursor.start }
       }
     }
+    if (needFix) {
+      this.setCursorRange(result)
+    }
+    return result
   }
 
   // topOffset is the line counts above cursor, and bottomOffset is line counts bellow cursor.