_______________________The research is based on an analysis of nearly 5000 English language studies published over the past three decades. Selah Hennessy for VOA NEWS, London. I'm Ray Kugel, VOA NEWS. You'll listen more on our website at voanews.com. ____________________该研究以过去30年间近5000项英文研究作为基础.VOA新闻通讯员Selah Hennessy伦敦报道. 以上是Ray Kugel为您带来的报道,有关更多新闻,欢迎访问我们的网站voanews.com.