add_action('pre_get_posts','test_post_function_calendar');
function test_post_function_calendar($query) {
    if
    ($query->is_main_query() &&
    ( tribe_is_month() && !is_tax() ) ||
    ( tribe_is_month() && is_tax() ) ||
    ( tribe_is_event() && !tribe_is_day() && !is_single() ) ||
    ( tribe_is_day() ) ||
    ( tribe_is_venue() )
    ) {

        $post_types = array();
        $post_types[] = $query->query_vars['post_type'];
        $post_types[] = 'post';
        $query->set('post_type',$post_types);
        //print_r($query->query_vars);
    }
}