Please read the following table in HTML format from a webpage and then answer the question in detail according to the table. Each table cell is defined by a <td> and a </td> tag. Each table row starts with a <tr> and ends with a </tr> tag. 'rowspan=m' and 'colspan=n' represents a cell spaning over 'm' rows and 'n' columns.

Webpage title:
Mohammed Aman
Table title:
Competition record
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Year </th><th colspan=1 rowspan=1 > Competition </th><th colspan=1 rowspan=1 > Venue </th><th colspan=1 rowspan=1 > Position </th><th colspan=1 rowspan=1 > Event </th><th colspan=1 rowspan=1 > Notes </th></tr>
<tr> <th colspan=6 rowspan=1 > Representing Ethiopia </th></tr>
<tr> <td colspan=1 rowspan=1 > 2009 </td><td colspan=1 rowspan=1 > African Junior Championships </td><td colspan=1 rowspan=1 > Bambous, Mauritius </td><td colspan=1 rowspan=1 > 1st </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:48.82 </td></tr>
<tr> <td colspan=1 rowspan=1 > 2010 </td><td colspan=1 rowspan=1 > Youth Olympic Games </td><td colspan=1 rowspan=1 > Singapore </td><td colspan=1 rowspan=1 > 1st </td><td colspan=1 rowspan=1 > 1000 m </td><td colspan=1 rowspan=1 > 2:19.54 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=3 > 2011 </td><td colspan=1 rowspan=1 > African Junior Championships </td><td colspan=1 rowspan=1 > Gaborone, Botswana </td><td colspan=1 rowspan=1 > 1st </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:46.62 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > World Youth Championships </td><td colspan=1 rowspan=1 > Lille, France </td><td class="highlighted"  colspan=1 rowspan=1 > 2nd </td><td class="highlighted"  colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:44.68 </td></tr>
<tr> <td colspan=1 rowspan=1 > World Championships </td><td colspan=1 rowspan=1 > Daegu, South Korea </td><td colspan=1 rowspan=1 > 8th </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:45.93 </td></tr>
<tr> <td colspan=1 rowspan=2 > 2012 </td><td colspan=1 rowspan=1 > World Indoor Championships </td><td colspan=1 rowspan=1 > Istanbul, Turkey </td><td colspan=1 rowspan=1 > 1st </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:48.36 </td></tr>
<tr> <td colspan=1 rowspan=1 > Olympic Games </td><td colspan=1 rowspan=1 > London, United Kingdom </td><td colspan=1 rowspan=1 > 6th </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:43.20 </td></tr>
<tr> <td colspan=1 rowspan=1 > 2013 </td><td colspan=1 rowspan=1 > World Championships </td><td colspan=1 rowspan=1 > Moscow, Russia </td><td colspan=1 rowspan=1 > 1st </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:43.31 </td></tr>
<tr> <td colspan=1 rowspan=2 > 2014 </td><td colspan=1 rowspan=1 > World Indoor Championships </td><td colspan=1 rowspan=1 > Sopot, Poland </td><td colspan=1 rowspan=1 > 1st </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:46.40 </td></tr>
<tr> <td colspan=1 rowspan=1 > African Championships </td><td colspan=1 rowspan=1 > Marrakech, Morocco </td><td colspan=1 rowspan=1 > 2nd </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:48.74 </td></tr>
<tr> <td colspan=1 rowspan=1 > 2015 </td><td colspan=1 rowspan=1 > World Championships </td><td colspan=1 rowspan=1 > Beijing, China </td><td colspan=1 rowspan=1 > — </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > DQ </td></tr>
<tr> <td colspan=1 rowspan=2 > 2016 </td><td colspan=1 rowspan=1 > World Indoor Championships </td><td colspan=1 rowspan=1 > Portland, United States </td><td colspan=1 rowspan=1 > 4th </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:47.97 </td></tr>
<tr> <td colspan=1 rowspan=1 > Olympic Games </td><td colspan=1 rowspan=1 > Rio de Janeiro, Brazil </td><td colspan=1 rowspan=1 > 18th (sf) </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:46.14 </td></tr>
<tr> <td colspan=1 rowspan=1 > 2017 </td><td colspan=1 rowspan=1 > World Championships </td><td colspan=1 rowspan=1 > London, United Kingdom </td><td colspan=1 rowspan=1 > 6th </td><td colspan=1 rowspan=1 > 800 m </td><td colspan=1 rowspan=1 > 1:46:06 </td></tr>
</table>
Question:
How did Mohammed Aman perform in his only event at the 2011 World Youth Championships?
Answer:
Mohammed Aman won a silver medal in the 800 m at the 2011 World Youth Championships.