This was worse than‘a terrible secret; this was a real skeleton! But George was unsympathetic. ‘Oh, that,'he said with a smile as if he were talking about an old friend. ‘That's Sebastian. You forget that I was a medical student once upon a time.'

　　19. This was worse than a terrible secret; this was a real skeleton!

　　这是比 “骇人听闻的秘密 ”更加惊人的东西，这是一具真正的骷髅啊!

　　语言点:句子结构分析:分号之后的内容为补充说明，解释“为什么骇人听闻”。

　　20. But George was unsympathetic.

　　但乔治却无动于衷。

　　语言点:句子结构分析:but引导的句子与上文的说法形成转折，引出下文George对这件事情的不同看法。

　　21. ‘Oh, that,’he said with a smile as if he were talking about an old friend.

　　“噢，是它呀!他笑着说道，俨然在谈论一位老朋友。

　　语言点1:句子结构分析:that指代上文中提到的skeleton。as if引导虚拟语气—“好像在谈论一位老朋友”。

　　语言点2:said with a smile的意思是“笑着说”，with a smile作方式状语，指的是“以笑的方式说”。

　　22. ‘That’s Sebastian. You forget that I was a medical student once upon a time.’

　　“那是塞巴斯蒂安。你忘了我以前是学医的了。”

　　语言点1:句子结构分析:that引导宾语从句，说明forget的内容是什么。

　　语言点2:once upon a time指的是“过去，曾经”，即以前的事情。