Original: Most people think of nerds as quiet, diffident people. In ordinary social situations they are — as quiet and diffident as the star quarterback would be if he found himself in the middle of a physics symposium.
Breaking down the second sentence Chinese translation, it seems like:
在通常的社交場合下 - in ordinary social situations 比如物理學研討會中 - for example in a physics symposium 書獃子確實是那樣 - nerds really are like that 就像橄欖球場上的四分衛一樣 - just like a football quarterback
The ordering feels really weird, so I'm not sure if I didn't know the original English if I could derive the same meaning from the Chinese sentence.