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:
Joseph Nzau
Table title:
Achievements
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 Kenya </th></tr>
<tr> <td colspan=1 rowspan=1 > 1982 </td><td colspan=1 rowspan=1 > Chicago Marathon </td><td colspan=1 rowspan=1 > Chicago, United States </td><td colspan=1 rowspan=1 > 2nd </td><td colspan=1 rowspan=1 > Marathon </td><td colspan=1 rowspan=1 > 2:11:40 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 1983 </td><td class="highlighted"  colspan=1 rowspan=1 > Chicago Marathon </td><td colspan=1 rowspan=1 > Chicago, United States </td><td class="highlighted"  colspan=1 rowspan=1 > 1st </td><td colspan=1 rowspan=1 > Marathon </td><td colspan=1 rowspan=1 > 2:09:44 </td></tr>
<tr> <td colspan=1 rowspan=3 > 1984 </td><td colspan=1 rowspan=1 > Los Angeles Marathon </td><td colspan=1 rowspan=1 > Los Angeles, United States </td><td colspan=1 rowspan=1 > 2nd </td><td colspan=1 rowspan=1 > Marathon </td><td colspan=1 rowspan=1 > 2:10:40 </td></tr>
<tr> <td colspan=1 rowspan=2 > Olympic Games </td><td colspan=1 rowspan=2 > Los Angeles, United States </td><td colspan=1 rowspan=1 > 14th </td><td colspan=1 rowspan=1 > 10,000 m </td><td colspan=1 rowspan=1 > 28:32.57 </td></tr>
<tr> <td colspan=1 rowspan=1 > 7th </td><td colspan=1 rowspan=1 > Marathon </td><td colspan=1 rowspan=1 > 2:11:28 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 1990 </td><td class="highlighted"  colspan=1 rowspan=1 > Belgrade Marathon </td><td colspan=1 rowspan=1 > Belgrade, FR Yugoslavia </td><td class="highlighted"  colspan=1 rowspan=1 > 1st </td><td colspan=1 rowspan=1 > Marathon </td><td colspan=1 rowspan=1 > 2:19:32 </td></tr>
</table>
Question:
What two marathons did Joseph Nzau win, and what years were each marathon?
Answer:
Nzau won the 1983 Chicago Marathon and the 1990 Belgrade Marathon.