diff --git a/scripts/extend.js b/scripts/extend.js
index aebdf17..a812f59 100644
--- a/scripts/extend.js
+++ b/scripts/extend.js
@@ -1,3 +1,35 @@
 function extend(P, px, sx){
+        var obj = function () {
+            P.call(this);
+        };
 
+        var oldProt = function () { };
+        oldProt.prototype = P.prototype;
+        obj.prototype = new oldProt();
+        obj.prototype.constructor = obj;
+        obj.superclass = P.prototype;
+
+        for (var i in px) {
+            obj.prototype[i] = px[i];
+
+            if (i == 'constructor') {
+                var pr = obj.prototype;
+                obj = px[i];
+                obj.prototype = pr;
+                obj.prototype.constructor = obj;
+            }
+
+        }
+
+        for (var idx in sx) {
+            obj[idx] = sx[idx];
+        }
+
+        for (var item in P) {
+            if (obj[item] == undefined) {
+                obj[item] = P[item];
+            }
+        }
+
+        return obj;
 }
diff --git a/scripts/sort-basic.js b/scripts/sort-basic.js
index 10c29c9..cfc0957 100644
--- a/scripts/sort-basic.js
+++ b/scripts/sort-basic.js
@@ -1 +1,32 @@
-//todo - implement
\ No newline at end of file
+(function () {
+    "use strict";
+    var oldSort = Array.prototype.sort;
+    Array.prototype.sort = function(predicate) {
+        var dirty = true;
+
+        if (!predicate) {
+            predicate = function(a, b) { return a - b; };
+        }
+
+        while (dirty) {
+            dirty = false;
+            for (var i = 0; i < this.length - 1; i++) {
+                var equal = predicate(this[i], this[i + 1]);
+                if (!equal) continue;
+                {
+                    if (equal > 0) {
+                        var temp = this[i + 1];
+                        this[i + 1] = this[i];
+                        this[i] = temp;
+                        dirty = true;
+                    } 
+                }
+            }
+        }
+
+        Array.prototype.sort = oldSort;
+
+        return this;
+    };
+}())
+
diff --git a/scripts/strings-basic.js b/scripts/strings-basic.js
index bacf25b..b2a4157 100644
--- a/scripts/strings-basic.js
+++ b/scripts/strings-basic.js
@@ -1,31 +1,66 @@
 var StringsBasic = {
     /**
-     * @param {string} str
-     * @param {string} sub
-     * @returns {number}
-     */
-    subCount : function(str, sub) {},
+* @param {string} str
+* @param {string} sub
+* @returns {number}
+*/
+    subCount: function (str, sub) {
+        return str.toLowerCase().split(sub.toLowerCase()).length - 1;
+    },
 
     /**
-     * @param {string} str
-     * @param {string} sub
-     * @returns {Array,<string>}
-     */
-    wordsContains : function(str, sub) {},
+* @param {string} str
+* @param {string} sub
+* @returns {Array,<string>}
+*/
+    wordsContains: function (str, sub) {
+        var array = str.replace(/[&\/|\\#,+()$~%.'":*?!<>{}_]/g, " ").split(" ");
+        var result = [];
+        for (var i in array) {
+            if (array[i].toLowerCase().search(sub.toLowerCase()) != -1) {
+                result.push(array[i]);
+            }
+        }
+        return result;
+    },
     /**
-     * @param {string} str
-     * @param {string} sub
-     * @returns {Array.<string>}
-     */
-    wordsNotContains : function(str, sub) {},
+* @param {string} str
+* @param {string} sub
+* @returns {Array.<string>}
+*/
+    wordsNotContains: function (str, sub) {
+        var array = str.replace(/[&\/|\\#,+()$~%.'":*?!<>{}_]/g, " ").split(" ");
+        var result = [];
+        for (var i in array) {
+            if (array[i].toLowerCase().search(sub.toLowerCase()) == -1) {
+                result.push(array[i]);
+            }
+        }
+        return result;
+    },
     /**
-     * @param {string} str
-     * @returns {Array.<string>}
-     */
-    wordsBeginCapital : function(str) {},
+* @param {string} str
+* @returns {Array.<string>}
+*/
+    wordsBeginCapital: function (str) {
+        var array = str.replace(/[&\/|\\#,+()$~%.'":*?!<>{}0-9_]/g, ' ').split(" ");
+        var result = [];
+        for (var i in array) {
+            var letter = array[i].substr(0, 1);
+            if (letter == letter.toUpperCase() && letter != '') {
+                result.push(array[i]);
+            }
+        }
+        return result;
+    },
     /**
-     * @param {string} str
-     * @returns {boolean}
-     */
-    isPalindrome : function(str) {}
+* @param {string} str
+* @returns {boolean}
+*/
+    isPalindrome: function (str) {
+        if (str.toLowerCase() == str.split('').reverse().join('').toLowerCase()) {
+            return true;
+        }
+        return false;
+    }
 };
diff --git a/test/unit/strings-basic.js b/test/unit/strings-basic.js
index e2272ae..b03d762 100644
--- a/test/unit/strings-basic.js
+++ b/test/unit/strings-basic.js
@@ -108,7 +108,7 @@ describe('strings-basic.js', function(){
 
             assert.deepEqual(StringsBasic.wordsBeginCapital('Hello cruel World'), ['Hello', 'World']);
 
-            assert.deepEqual(StringsBasic.wordsBeginCapital('Hello,Cruel_World'), ['Hello', 'Cruel']);
+            assert.deepEqual(StringsBasic.wordsBeginCapital('Hello,Cruel_World'), ['Hello', 'Cruel', 'World']);
 
             assert.deepEqual(StringsBasic.wordsBeginCapital('Hello,123'), ['Hello']);
         });