在vb.net中使用Word错误

Question

此VB.net代码产生未定义的错误。

$ch = curl_init ( "https://www.google.com.ar/search?q=1+usd+to+ars" );
curl_setopt ( $ch, CURLOPT_RETURNTRANSFER, true );
curl_setopt ( $ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13');
$output = curl_exec ( $ch );
echo $output;
curl_close ( $ch );

添加了行：Dim oWord As Word.Application Dim oDoc As Word.Document

我做错了什么或我错过了什么？