I added a checkbox in my xml code and i got a very wierd output. I m a begginer please help me

So i added this check box in my XML file . I didnt get a checkbox in my output. I got something wierd. Im a beginner here. CAn someonehelp me? I have put my XML code below and the image of how the checkbox looks like in the attachments. Please someone help me .

    <?xml version="1.0" encoding="utf-8"?>
   <RelativeLayout       xmlns:android="http://ift.tt/nIICcg"
xmlns:tools="http://ift.tt/LrGmb4"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.android.myapplication.MainActivity">

<TextView
    android:id="@+id/hello_world"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Hello World!" />
<CheckBox
    android:id="@+id/checkBox1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Do you like Tutorials Point"
    android:layout_alignTop="@+id/hello_world"
    android:layout_centerHorizontal="true" />

I have attached a photo of the output I am getting. Please someone help me I am a beginner only .

enter image description here