diff --git a/src/task_1/index.js b/src/task_1/index.js
index 2abfd00..3b3b332 100644
--- a/src/task_1/index.js
+++ b/src/task_1/index.js
@@ -15,6 +15,13 @@
 @param {number} hours - Час
 @param {number} minutes - Минуты
  */
-function Time(hours, minutes) { };
+function Time(hours, minutes) {
+	if(hours > 23 || hours < 0 || minutes > 60 || minutes < 0) throw new Error('Incorrect time');
+	this.hours = hours;
+	this.minutes = minutes;
+	this.isEarlier = time => time.timeInMinutes() > this.timeInMinutes(); 
+	this.isLater = time => time.timeInMinutes() < this.timeInMinutes(); 
+	this.timeInMinutes = () => this.minutes + this.hours * 60;
+}
 
 module.exports.Time = Time;
diff --git a/src/task_2/index.js b/src/task_2/index.js
index f20d7ee..4c2bdfa 100644
--- a/src/task_2/index.js
+++ b/src/task_2/index.js
@@ -17,6 +17,15 @@ const { Time } = require('../task_1/index');
 @param {Time} startTime - Время начала встречи
 @param {Time} endTime - Время конца встречи
  */
-function Meeting(meetingDate, startTime, endTime) { };
+function Meeting(meetingDate, startTime, endTime) { 
+	if(!startTime || !endTime || startTime.timeInMinutes() > endTime.timeInMinutes() || 
+		startTime.timeInMinutes() < 480 || endTime.timeInMinutes() > 1140) throw new Error('Incorrect meeting')
+	this.meetingDate = meetingDate;
+	this.startTime = startTime;
+	this.endTime = endTime;
+	this.isMeetingInTimeRange = (start, end) => 
+		this.endTime.timeInMinutes() >= start.timeInMinutes() && this.startTime.timeInMinutes() <= end.timeInMinutes() ||
+		this.startTime.timeInMinutes() <= end.timeInMinutes() && this.endTime.timeInMinutes() >= start.timeInMinutes();
+}
 
 module.exports.Meeting = Meeting;
diff --git a/src/task_3/index.js b/src/task_3/index.js
index 4212ffa..021423f 100644
--- a/src/task_3/index.js
+++ b/src/task_3/index.js
@@ -11,6 +11,13 @@
 @param {Date} vacationEndDate - Время конца отпуска
  */
 
-function Vacation(vacationStartDate, vacationEndDate) { };
+function Vacation(vacationStartDate, vacationEndDate) {
+	if(!vacationStartDate || !vacationEndDate ||
+		Number(vacationStartDate) >= Number(vacationEndDate)) throw new Error('Incorrect vacation')
+	this.vacationStartDate = vacationStartDate;
+	this.vacationEndDate = vacationEndDate;
+	this.isDateInVacation = date => 
+		Number(date) >= Number(vacationStartDate) && Number(date) <= Number(vacationEndDate);  
+}
 
 module.exports.Vacation = Vacation;
diff --git a/src/task_4/index.js b/src/task_4/index.js
index cae825a..0d4d666 100644
--- a/src/task_4/index.js
+++ b/src/task_4/index.js
@@ -12,6 +12,9 @@ const { Vacation } = require('../task_3/index');
 @param {Array<Vacation>} vacations - Массив отпусков
  */
 
-function Organaizer(meetings, vacations) { };
+function Organaizer(meetings, vacations) {
+	this.meetings = meetings;
+	this.vacations = vacations;
+ };
 
 module.exports.Organaizer = Organaizer;