Parse error: syntax error, unexpected ''tax_query'' in wordpress

hi i want to display posts by term. first the code display all the posts:

 $aProjectArgs = array(
            'post_type' => 'uni_project',
            'posts_per_page' => -1,
            'orderby' => 'menu_order',
            'order' => 'asc'
);

so i add another part of code to display posts by term:

$aProjectArgs = array(
            'post_type' => 'uni_project',
            'posts_per_page' => -1,
            'orderby' => 'menu_order',
            'order' => 'asc'
            'tax_query' => array(
    array(
    'taxonomy' => 'post_tag',
    'field' => 'id',
    'terms' => 43
     )
  )
        );

but its not working its give me an error message:Parse error: syntax error, unexpected ''tax_query''

can someone help me?