为啥我这一直报错？

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
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=".MainActivity" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
<TextView
andriod:layout_width="fill_parent"
andriod:layout_height="warp_content"
andriod:text="This is my first Andriod Application!"/>
<Button
android:layout_width="fill_parent"
andriod:layout_height="wrap_content"
andriod:text="And this is a clickable button!"/>
</RelativeLayout>