その専門家が言うには、容疑者はUSの南部に住んでいるか、そこで育ったに違いない。いくら巧みに彼本来のアクセントを隠そうとしても、専門家をごまかすことは出来ないと。
The expert said the suspect must live in or must have been brought up in the southern part of the US and that no matter how skillfully the suspect tried to hide his native accent, he couldn't fool the expert.