$en = '{"q": "","source": "","target": "","format": "","api_key": ""}';
$options = array(
  'http'=>array(
    'method'=>"POST",
    'header'=>"Content-Type: application/json",
    'content' => $en
  )
);
$context = stream_context_create($options);
$data = file_get_contents("https://xxxxx.xxxxx/xxxxx", false, $context);