diff --git a/src/main/java/net/micode/notes/gtask/data/MetaData.java b/src/main/java/net/micode/notes/gtask/data/MetaData.java
index e7f8fb7..e713ad7 100644
--- a/src/main/java/net/micode/notes/gtask/data/MetaData.java
+++ b/src/main/java/net/micode/notes/gtask/data/MetaData.java
@@ -24,8 +24,8 @@ import net.micode.notes.tool.GTaskStringUtils;
 import org.json.JSONException;
 import org.json.JSONObject;
 
-
-public class MetaData extends Task {
+//主要是定义用于处理元数据
+public class MetaData extends Task {//继承task，是task的子类
     private final static String TAG = MetaData.class.getSimpleName();
 
     private String mRelatedGid = null;
@@ -34,7 +34,7 @@ public class MetaData extends Task {
         try {
             metaInfo.put(GTaskStringUtils.META_HEAD_GTASK_ID, gid);
         } catch (JSONException e) {
-            Log.e(TAG, "failed to put related gid");
+            Log.e(TAG, "failed to put related gid");//记录错误日志
         }
         setNotes(metaInfo.toString());
         setName(GTaskStringUtils.META_NOTE_NAME);
@@ -47,10 +47,10 @@ public class MetaData extends Task {
     @Override
     public boolean isWorthSaving() {
         return getNotes() != null;
-    }
+    }//用于判断数据是否值得保存
 
     @Override
-    public void setContentByRemoteJSON(JSONObject js) {//用远程的json
+    public void setContentByRemoteJSON(JSONObject js) {//用远程的json设置内容，基础操作元
         super.setContentByRemoteJSON(js);
         if (getNotes() != null) {
             try {
@@ -66,7 +66,7 @@ public class MetaData extends Task {
     @Override
     public void setContentByLocalJSON(JSONObject js) {//这几个函数都是通过一部分已知的项推算其他未知的
         // this function should not be called
-        throw new IllegalAccessError("MetaData:setContentByLocalJSON should not be called");
+        throw new IllegalAccessError("MetaData:setContentByLocalJSON should not be called");//抛出了IllegalAccessError异常，表明它不应该被直接调用
     }
 
     @Override
diff --git a/src/main/java/net/micode/notes/gtask/data/Node.java b/src/main/java/net/micode/notes/gtask/data/Node.java
index 3a11067..c520c06 100644
--- a/src/main/java/net/micode/notes/gtask/data/Node.java
+++ b/src/main/java/net/micode/notes/gtask/data/Node.java
@@ -20,7 +20,7 @@ import android.database.Cursor;
 
 import org.json.JSONObject;
 
-public abstract class Node {
+public abstract class Node {//主要定义一些获取属性值的方法
     public static final int SYNC_ACTION_NONE = 0;
 
     public static final int SYNC_ACTION_ADD_REMOTE = 1;
@@ -38,6 +38,7 @@ public abstract class Node {
     public static final int SYNC_ACTION_UPDATE_CONFLICT = 7;
 
     public static final int SYNC_ACTION_ERROR = 8;
+    //为不同的同步类型添加调用编号
 
     private String mGid;
 
@@ -45,7 +46,7 @@ public abstract class Node {
 
     private long mLastModified;
 
-    private boolean mDeleted;
+    private boolean mDeleted;//设置基础值，定义获取参数的方法
 
     public Node() {
         mGid = null;
diff --git a/src/main/java/net/micode/notes/gtask/data/SqlData.java b/src/main/java/net/micode/notes/gtask/data/SqlData.java
index d3ec3be..7fdfd17 100644
--- a/src/main/java/net/micode/notes/gtask/data/SqlData.java
+++ b/src/main/java/net/micode/notes/gtask/data/SqlData.java
@@ -71,9 +71,9 @@ public class SqlData {
 
     private ContentValues mDiffDataValues;
 
-    public SqlData(Context context) {
+    public SqlData(Context context) {//初始化对象，用于存储数据
         mContentResolver = context.getContentResolver();
-        mIsCreate = true;
+        mIsCreate = true;//一类型的变量为true
         mDataId = INVALID_ID;
         mDataMimeType = DataConstants.NOTE;
         mDataContent = "";
@@ -82,14 +82,14 @@ public class SqlData {
         mDiffDataValues = new ContentValues();
     }
 
-    public SqlData(Context context, Cursor c) {
+    public SqlData(Context context, Cursor c) {//同样是存储数据，另外定义支持冲cursor读入
         mContentResolver = context.getContentResolver();
-        mIsCreate = false;
+        mIsCreate = false;//二类型的变量为false
         loadFromCursor(c);
         mDiffDataValues = new ContentValues();
     }
 
-    private void loadFromCursor(Cursor c) {
+    private void loadFromCursor(Cursor c) {//上面用到的从cursor读取的函数，从存储的各个列获取数据
         mDataId = c.getLong(DATA_ID_COLUMN);
         mDataMimeType = c.getString(DATA_MIME_TYPE_COLUMN);
         mDataContent = c.getString(DATA_CONTENT_COLUMN);
@@ -97,9 +97,9 @@ public class SqlData {
         mDataContentData3 = c.getString(DATA_CONTENT_DATA_3_COLUMN);
     }
 
-    public void setContent(JSONObject js) throws JSONException {
-        long dataId = js.has(DataColumns.ID) ? js.getLong(DataColumns.ID) : INVALID_ID;
-        if (mIsCreate || mDataId != dataId) {
+    public void setContent(@androidx.annotation.NonNull JSONObject js) throws JSONException {//获取json类型的参数，并且根据它更新自定义的数据单元中的值
+        long dataId = js.has(DataColumns.ID) ? js.getLong(DataColumns.ID) : INVALID_ID;//如果有id直接赋值，没有则需要在获取
+        if (mIsCreate || mDataId != dataId) {//初始未设置的数据单元通过它设置内容，通过cursor产生的数据元可通过它完成更新
             mDiffDataValues.put(DataColumns.ID, dataId);
         }
         mDataId = dataId;
@@ -131,7 +131,7 @@ public class SqlData {
     }
 
     public JSONObject getContent() throws JSONException {
-        if (mIsCreate) {
+        if (mIsCreate) {//同样的只有通过cursor产生的数据单元可通过这个函数获取数据
             Log.e(TAG, "it seems that we haven't created this in database yet");
             return null;
         }
@@ -144,7 +144,7 @@ public class SqlData {
         return js;
     }
 
-    public void commit(long noteId, boolean validateVersion, long version) {
+    public void commit(long noteId, boolean validateVersion, long version) {//提交数据，并且打上类似于标签的版本号以及验证值
 
         if (mIsCreate) {
             if (mDataId == INVALID_ID && mDiffDataValues.containsKey(DataColumns.ID)) {
@@ -162,10 +162,10 @@ public class SqlData {
         } else {
             if (mDiffDataValues.size() > 0) {
                 int result = 0;
-                if (!validateVersion) {
+                if (!validateVersion) { // 不验证版本的情况下，直接使用ContentResolver更新指定ID的数据
                     result = mContentResolver.update(ContentUris.withAppendedId(
                             Notes.CONTENT_DATA_URI, mDataId), mDiffDataValues, null, null);
-                } else {
+                } else { // 需要验证版本的情况下，使用ContentResolver进行条件更新操作
                     result = mContentResolver.update(ContentUris.withAppendedId(
                             Notes.CONTENT_DATA_URI, mDataId), mDiffDataValues,
                             " ? in (SELECT " + NoteColumns.ID + " FROM " + TABLE.NOTE
diff --git a/src/main/java/net/micode/notes/gtask/data/SqlNote.java b/src/main/java/net/micode/notes/gtask/data/SqlNote.java
index 79a4095..48891a6 100644
--- a/src/main/java/net/micode/notes/gtask/data/SqlNote.java
+++ b/src/main/java/net/micode/notes/gtask/data/SqlNote.java
@@ -122,7 +122,7 @@ public class SqlNote {
 
     private ArrayList<SqlData> mDataList;
 
-    public SqlNote(Context context) {
+    public SqlNote(Context context) {//定义数据单元存储数据
         mContext = context;
         mContentResolver = context.getContentResolver();
         mIsCreate = true;
@@ -135,7 +135,7 @@ public class SqlNote {
         mParentId = 0;
         mSnippet = "";
         mType = Notes.TYPE_NOTE;
-        mWidgetId = AppWidgetManager.INVALID_APPWIDGET_ID;
+        mWidgetId = AppWidgetManager.INVALID_APPWIDGET_ID;//直接从设置的属性中获取值
         mWidgetType = Notes.TYPE_WIDGET_INVALIDE;
         mOriginParent = 0;
         mVersion = 0;
@@ -147,14 +147,14 @@ public class SqlNote {
         mContext = context;
         mContentResolver = context.getContentResolver();
         mIsCreate = false;
-        loadFromCursor(c);
+        loadFromCursor(c);//从cursor中直接获取变量值
         mDataList = new ArrayList<SqlData>();
         if (mType == Notes.TYPE_NOTE)
             loadDataContent();
         mDiffNoteValues = new ContentValues();
     }
 
-    public SqlNote(Context context, long id) {
+    public SqlNote(Context context, long id) {//根据id初始化数据单元
         mContext = context;
         mContentResolver = context.getContentResolver();
         mIsCreate = false;
@@ -175,7 +175,7 @@ public class SqlNote {
                     }, null);
             if (c != null) {
                 c.moveToNext();
-                loadFromCursor(c);
+                loadFromCursor(c);//通过调用减少重复代码编写
             } else {
                 Log.w(TAG, "loadFromCursor: cursor = null");
             }
@@ -185,7 +185,7 @@ public class SqlNote {
         }
     }
 
-    private void loadFromCursor(Cursor c) {
+    private void loadFromCursor(Cursor c) {//直接使用get获得变量值
         mId = c.getLong(ID_COLUMN);
         mAlertDate = c.getLong(ALERTED_DATE_COLUMN);
         mBgColorId = c.getInt(BG_COLOR_ID_COLUMN);
@@ -200,7 +200,7 @@ public class SqlNote {
         mVersion = c.getLong(VERSION_COLUMN);
     }
 
-    private void loadDataContent() {
+    private void loadDataContent() {//这个函数判别查询的数据是否存在，并且读取到数据列表中存储
         Cursor c = null;
         mDataList.clear();
         try {
@@ -210,12 +210,12 @@ public class SqlNote {
                     }, null);
             if (c != null) {
                 if (c.getCount() == 0) {
-                    Log.w(TAG, "it seems that the note has not data");
+                    Log.w(TAG, "it seems that the note has not data");//遇到文件为空抛出对应的异常
                     return;
                 }
                 while (c.moveToNext()) {
                     SqlData data = new SqlData(mContext, c);
-                    mDataList.add(data);
+                    mDataList.add(data);//向Datalist中加入读取到的数据
                 }
             } else {
                 Log.w(TAG, "loadDataContent: cursor = null");
@@ -226,7 +226,8 @@ public class SqlNote {
         }
     }
 
-    public boolean setContent(JSONObject js) {
+    public boolean setContent(JSONObject js) {//设置数据单元中变量的值
+        //如果所需的值存在，直接赋值使用，否则再先进行一步读取
         try {
             JSONObject note = js.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
             if (note.getInt(NoteColumns.TYPE) == Notes.TYPE_SYSTEM) {
@@ -359,7 +360,7 @@ public class SqlNote {
         return true;
     }
 
-    public JSONObject getContent() {
+    public JSONObject getContent() {//直接读取的方式将所需的数据读到对应变量
         try {
             JSONObject js = new JSONObject();
 
@@ -412,6 +413,7 @@ public class SqlNote {
         mDiffNoteValues.put(NoteColumns.PARENT_ID, id);
     }
 
+    //定义一些简单的获取取值的方法
     public void setGtaskId(String gid) {
         mDiffNoteValues.put(NoteColumns.GTASK_ID, gid);
     }
@@ -440,7 +442,7 @@ public class SqlNote {
         return mType == Notes.TYPE_NOTE;
     }
 
-    public void commit(boolean validateVersion) {
+    public void commit(boolean validateVersion) {//将数据做一定修改提交
         if (mIsCreate) {
             if (mId == INVALID_ID && mDiffNoteValues.containsKey(NoteColumns.ID)) {
                 mDiffNoteValues.remove(NoteColumns.ID);