diff --git a/source/MetaDataModel.cpp b/source/MetaDataModel.cpp
index ea04dfb..026d37c 100644
--- a/source/MetaDataModel.cpp
+++ b/source/MetaDataModel.cpp
@@ -40,12 +40,71 @@ QVariant MetaDataModel::data(const QModelIndex &index, int role) const
 	return QVariant();
 }
 
+Qt::ItemFlags MetaDataModel::flags(const QModelIndex &index) const
+{
+	return QAbstractTableModel::flags(index) | Qt::ItemIsEditable;
+}
+
+bool MetaDataModel::setData(
+	const QModelIndex &index, const QVariant &value, int role)
+{
+	if (role != Qt::EditRole)
+	{
+		return QAbstractTableModel::setData(index, value, role);
+	}
+
+	bool valueChanged = false;
+
+	switch (index.column())
+	{
+		case 0:
+			if (value.toString() != m_participant)
+			{
+				m_participant = value.toString();
+				valueChanged = true;
+			}
+			break;
+		case 1:
+			if (value.toString() != m_instructor)
+			{
+				m_instructor = value.toString();
+				valueChanged = true;
+			}
+			break;
+		case 2:
+			if (value.toDate() != m_dateOfTest)
+			{
+				m_dateOfTest = value.toDate();
+				valueChanged = true;
+			}
+			break;
+		case 3:
+			if (value.toDate() != m_dateOfBirth)
+			{
+				m_dateOfBirth = value.toDate();
+				valueChanged = true;
+			}
+			break;
+		case 4:
+			if (value.toString() != m_remarks)
+			{
+				m_remarks = value.toString();
+				valueChanged = true;
+			}
+			break;
+		default:
+			break;
+	}
+
+	return valueChanged;
+}
+
 void MetaDataModel::write(QJsonObject &json) const
 {
 	json["participant name"] = m_participant;
 	json["instructor name"] = m_instructor;
-	json["date of birth"] = m_dateOfBirth.toString(Qt::TextDate);
-	json["date of test"] = m_dateOfTest.toString(Qt::TextDate);
+	json["date of birth"] = m_dateOfBirth.toString(Qt::ISODate);
+	json["date of test"] = m_dateOfTest.toString(Qt::ISODate);
 	json["remarks"] = m_remarks;
 }
 
@@ -66,13 +125,13 @@ void MetaDataModel::read(const QJsonObject &json)
 	const auto &dateOfBirth = json["date of birth"];
 	if (dateOfBirth.isString())
 	{
-		m_dateOfBirth.fromString(dateOfBirth.toString());
+		m_dateOfBirth = QDate::fromString(dateOfBirth.toString(), Qt::ISODate);
 	}
 
 	const auto &dateOfTest = json["date of test"];
 	if (dateOfTest.isString())
 	{
-		m_dateOfTest.fromString(dateOfTest.toString());
+		m_dateOfTest = QDate::fromString(dateOfTest.toString(), Qt::ISODate);
 	}
 
 	const auto &remarks = json["remarks"];
diff --git a/source/MetaDataModel.h b/source/MetaDataModel.h
index db179ae..94de6a3 100644
--- a/source/MetaDataModel.h
+++ b/source/MetaDataModel.h
@@ -22,6 +22,9 @@ public:
 	int columnCount(const QModelIndex &parent = QModelIndex()) const override;
 	QVariant data(
 		const QModelIndex &index, int role = Qt::DisplayRole) const override;
+	Qt::ItemFlags flags(const QModelIndex &index) const override;
+	bool setData(const QModelIndex &index, const QVariant &value,
+		int role = Qt::EditRole) override;
 
 	void write(QJsonObject &json) const;
 	void read(const QJsonObject &json);
diff --git a/source/mainwindow.cpp b/source/mainwindow.cpp
index 055f656..3109e17 100644
--- a/source/mainwindow.cpp
+++ b/source/mainwindow.cpp
@@ -28,10 +28,8 @@ MainWindow::MainWindow(QWidget *parent)
 	m_widgetMapper->addMapping(ui->lineEdit_2, 1);
 	m_widgetMapper->addMapping(ui->dateEdit, 2);
 	m_widgetMapper->addMapping(ui->dateEdit_2, 3);
-	m_widgetMapper->addMapping(ui->textEdit, 4);
+	m_widgetMapper->addMapping(ui->plainTextEdit, 4);
 	m_widgetMapper->toFirst();
-
-	connect(ui->calendarWidget, SIGNAL(selectionChanged()), m_widgetMapper, SLOT(submit()));
 }
 
 MainWindow::~MainWindow()
diff --git a/source/mainwindow.ui b/source/mainwindow.ui
index 4165469..21c2d5a 100644
--- a/source/mainwindow.ui
+++ b/source/mainwindow.ui
@@ -42,45 +42,6 @@
          </property>
         </widget>
        </item>
-       <item row="2" column="1">
-        <widget class="QCalendarWidget" name="calendarWidget_2">
-         <property name="selectedDate">
-          <date>
-           <year>2018</year>
-           <month>9</month>
-           <day>10</day>
-          </date>
-         </property>
-         <property name="firstDayOfWeek">
-          <enum>Qt::Monday</enum>
-         </property>
-         <property name="horizontalHeaderFormat">
-          <enum>QCalendarWidget::ShortDayNames</enum>
-         </property>
-         <property name="verticalHeaderFormat">
-          <enum>QCalendarWidget::NoVerticalHeader</enum>
-         </property>
-        </widget>
-       </item>
-       <item row="2" column="3">
-        <widget class="QCalendarWidget" name="calendarWidget">
-         <property name="firstDayOfWeek">
-          <enum>Qt::Monday</enum>
-         </property>
-         <property name="gridVisible">
-          <bool>false</bool>
-         </property>
-         <property name="verticalHeaderFormat">
-          <enum>QCalendarWidget::NoVerticalHeader</enum>
-         </property>
-         <property name="navigationBarVisible">
-          <bool>true</bool>
-         </property>
-         <property name="dateEditEnabled">
-          <bool>true</bool>
-         </property>
-        </widget>
-       </item>
        <item row="1" column="3">
         <widget class="QLineEdit" name="lineEdit_2"/>
        </item>
@@ -91,10 +52,10 @@
          </property>
         </widget>
        </item>
-       <item row="3" column="1">
+       <item row="2" column="1">
         <widget class="QDateEdit" name="dateEdit"/>
        </item>
-       <item row="3" column="3">
+       <item row="2" column="3">
         <widget class="QDateEdit" name="dateEdit_2"/>
        </item>
       </layout>
@@ -108,7 +69,7 @@
      </widget>
     </item>
     <item>
-     <widget class="QTextEdit" name="textEdit"/>
+     <widget class="QPlainTextEdit" name="plainTextEdit"/>
     </item>
    </layout>
   </widget>