However, one type of cancer puzzled the researchers.
然而某种类型的癌症困扰着这些研究人员。
___________________________________. But they wrote that they could not explain the connection.
____________________________。但是这些研究人员称他们无法解释这种关联。
The researchers also found that people who did heavier exercises had a slightly higher rate of skin cancer. This, they say, could be from more sun exposure.
这些研究人员还发现，运动量更大的人们患上皮肤癌的几率略高。他们表示，这可能是因为接受了更多的日照。
