diff --git a/src/main/java/net/micode/notes/data/Contact.java b/src/main/java/net/micode/notes/data/Contact.java
index d97ac5d..1e04184 100644
--- a/src/main/java/net/micode/notes/data/Contact.java
+++ b/src/main/java/net/micode/notes/data/Contact.java
@@ -25,24 +25,24 @@ import android.util.Log;
 
 import java.util.HashMap;
 
-public class Contact {
+public class Contact {//定义一个Contact类，类别标签为Contact，包含一个用于存储用户信息的HashMap
     private static HashMap<String, String> sContactCache;
     private static final String TAG = "Contact";
-
+//定义静态常量，用于查询指定联系人
     private static final String CALLER_ID_SELECTION = "PHONE_NUMBERS_EQUAL(" + Phone.NUMBER
     + ",?) AND " + Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'"
     + " AND " + Data.RAW_CONTACT_ID + " IN "
             + "(SELECT raw_contact_id "
             + " FROM phone_lookup"
             + " WHERE min_match = '+')";
-
+//定义一个静态方法getContact，可以通过Contact对象以及电话号码查询联系人。
     public static String getContact(Context context, String phoneNumber) {
-        if(sContactCache == null) {
+        if(sContactCache == null) {//不存在这个联系人则新建一个存储信息
             sContactCache = new HashMap<String, String>();
         }
 
-        if(sContactCache.containsKey(phoneNumber)) {
-            return sContactCache.get(phoneNumber);
+        if(sContactCache.containsKey(phoneNumber)) {//如果已经包含电话号码作为关键字对应的用户
+            return sContactCache.get(phoneNumber);//直接返回用户的名字，get返回名字
         }
 
         String selection = CALLER_ID_SELECTION.replace("+",
diff --git a/src/main/java/net/micode/notes/data/Notes.java b/src/main/java/net/micode/notes/data/Notes.java
index f240604..fddf75c 100644
--- a/src/main/java/net/micode/notes/data/Notes.java
+++ b/src/main/java/net/micode/notes/data/Notes.java
@@ -17,7 +17,7 @@
 package net.micode.notes.data;
 
 import android.net.Uri;
-public class Notes {
+public class Notes {//定义Nodes类，初始化参数，都赋值成静态量
     public static final String AUTHORITY = "micode_notes";
     public static final String TAG = "Notes";
     public static final int TYPE_NOTE     = 0;
@@ -54,14 +54,14 @@ public class Notes {
     /**
      * Uri to query all notes and folders
      */
-    public static final Uri CONTENT_NOTE_URI = Uri.parse("content://" + AUTHORITY + "/note");
+    public static final Uri CONTENT_NOTE_URI = Uri.parse("content://" + AUTHORITY + "/note");//指定笔记的路径
 
     /**
      * Uri to query data
      */
-    public static final Uri CONTENT_DATA_URI = Uri.parse("content://" + AUTHORITY + "/data");
+    public static final Uri CONTENT_DATA_URI = Uri.parse("content://" + AUTHORITY + "/data");//用于指定数据的路径，类似上面
 
-    public interface NoteColumns {
+    public interface NoteColumns {//定义笔记集ID、父集ID、创建日期，修改日期等等列名称以及类型，做初始化
         /**
          * The unique ID for a row
          * <P> Type: INTEGER (long) </P>
@@ -167,7 +167,7 @@ public class Notes {
         public static final String VERSION = "version";
     }
 
-    public interface DataColumns {
+    public interface DataColumns {//定义接口，给每行数据ID，类型，所属笔记集ID，内容数据等等做定义
         /**
          * The unique ID for a row
          * <P> Type: INTEGER (long) </P>
@@ -241,20 +241,20 @@ public class Notes {
         public static final String DATA5 = "data5";
     }
 
-    public static final class TextNote implements DataColumns {
+    public static final class TextNote implements DataColumns {//实现DataColumn接口，为数据库查询操作提供数据列名称
         /**
          * Mode to indicate the text in check list mode or not
          * <P> Type: Integer 1:check list mode 0: normal mode </P>
          */
         public static final String MODE = DATA1;
 
-        public static final int MODE_CHECK_LIST = 1;
+        public static final int MODE_CHECK_LIST = 1;//表示当前文本是否还处于检查列清单的模式
 
         public static final String CONTENT_TYPE = "vnd.android.cursor.dir/text_note";
 
         public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/text_note";
 
-        public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/text_note");
+        public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/text_note");//指定路径
     }
 
     public static final class CallNote implements DataColumns {