diff --git a/package-lock.json b/package-lock.json
index c6a18e7..09d470f 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -8,6 +8,11 @@
       "version": "1.20150623.0",
       "resolved": "https://registry.npmjs.org/tsc/-/tsc-1.20150623.0.tgz",
       "integrity": "sha1-Trw8d04WkUjLx2inNCUz8ILHpuU="
+    },
+    "typescript": {
+      "version": "4.2.3",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-4.2.3.tgz",
+      "integrity": "sha512-qOcYwxaByStAWrBf4x0fibwZvMRG+r4cQoTjbPtUlrWjBHbmCAww1i448U0GJ+3cNNEtebDteo/cHOR3xJ4wEw=="
     }
   }
 }
diff --git a/package.json b/package.json
index 0d703f8..33a40c3 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,8 @@
   },
   "homepage": "https://github.com/RTF-Angular-2021/ts-task-1#readme",
   "dependencies": {
-    "tsc": "^1.20150623.0"
+    "tsc": "^1.20150623.0",
+    "typescript": "^4.2.3"
   },
   "devDependencies": {}
 }
diff --git a/src/task_1/index.ts b/src/task_1/index.ts
index 3edb7b9..cf24a55 100644
--- a/src/task_1/index.ts
+++ b/src/task_1/index.ts
@@ -3,8 +3,8 @@
  * который написан в функции logObj компилировался и исполнялся корректно
 */
 
-type FooType = unknown;
-type BarType = unknown;
+type FooType = {stringProp: String, numberProp: Number, barObject: BarType};
+type BarType = {stringsArrayProp: Array<string>, numbersOrDatesArrayProp: Array<Date | number>, functionProp(flag: boolean): void};
 
 export const fooObjects: FooType[] = [
     {
diff --git a/src/task_2/index.ts b/src/task_2/index.ts
index 00b4939..e7bb5e1 100644
--- a/src/task_2/index.ts
+++ b/src/task_2/index.ts
@@ -71,6 +71,7 @@ const obj7: ThirdType = {
 const array = [obj1, obj2, obj3, obj4, obj5, obj6, obj7];
 
 function filter(array: Array<FirstType | SecondType | ThirdType>, type: string) {
+    return array.filter((x): x is FirstType | SecondType | ThirdType => typeof x === type);
 }
 
 filter(array, 'FirstType');
diff --git a/src/task_3/index.ts b/src/task_3/index.ts
index b7c9cdc..8a1e906 100644
--- a/src/task_3/index.ts
+++ b/src/task_3/index.ts
@@ -7,6 +7,10 @@
 */
 function add(x: string, y: string): string;
 function add(x: number, y: number): number;
+function add(x:any, y:any):any{
+    return x+y;
+};
+
 
 add('20', '21'); //2021
 add(20, 21); //41
\ No newline at end of file
diff --git a/src/task_4/index.ts b/src/task_4/index.ts
index e884df8..b9e86a2 100644
--- a/src/task_4/index.ts
+++ b/src/task_4/index.ts
@@ -12,3 +12,57 @@ type FooType = {
     a: number
     b: string
 };
+
+/*
+Приведу аналогию, пожалуй. Type это struct в C#, только не имеющий инициализатора/конструктора
+Class can implement Interface, types
+Class can be extended by Interface and classes
+Variable can implement type
+Variable cannot be extended by any of type or interface
+*/
+
+interface IAnimal{
+    DoSound(): void
+    name: string
+    sex: string //better enum
+}
+
+type DogType ={
+    breed: string;
+    name: string|Number;
+    doSound(): void;
+}
+
+class Dog implements IAnimal{
+    DoSound(): void {
+        console.log("Whoooff!");
+    }
+    name: "Axel";
+    sex: "Male";
+    breed: "HolyWater";
+}
+
+//But cannot compile class when extending type
+
+class DogT extends DogType{ //Compile error
+    doSound(): void {
+        throw new Error("Method not implemented.");
+    }
+    breed: string;
+    name: 21312;
+    
+}
+
+//At the same time, can compile class when implementing type
+
+class DogTI implements DogType{
+    doSound(): void {
+        throw new Error("Method not implemented.");
+    }
+    breed: string;
+    name: 21312;
+    
+}
+
+//type cannot be extended by another type or interface
+//Interface can be extended by another interface
\ No newline at end of file
diff --git a/src/task_5/index.ts b/src/task_5/index.ts
index ef3e0c0..988e02e 100644
--- a/src/task_5/index.ts
+++ b/src/task_5/index.ts
@@ -73,7 +73,7 @@ export function logPerson(person: Person) {
     console.log(` - ${person.name}, ${person.age}, ${additionalInformation}`);
 }
 
-export function filterUsers(persons: Person[], criteria: User): User[] {
+export function filterUsers(persons: Person[], criteria: {type?: string, name?: string, age?: number, occupation?: string}): User[] {
     return persons.filter(isUser).filter((user) => {
         const criteriaKeys = Object.keys(criteria);
         return criteriaKeys.every((fieldName) => {