I have been pondering over this problem for quite a long time but still couldn't puzzle it out.

我想这个问题想了很久，但还是想不出答案。

youdao

I saw him puzzle over a math problem.

我看见他正在苦心思索一道数学题。

youdao

Defining obesity has been a puzzle over the years due to the different conclusions that people come up with linking to the causes of the health problem.

肥胖的定义在这几年来已经成为了一个迷题，原因在于人们想出了各种可能引起健康问题的结论。

youdao

Defining obesity has been a puzzle over the years due to the different conclusions that people come up with linking to the causes of the health problem.

肥胖的定义在这几年来已经成为了一个迷题，原因在于人们想出了各种可能引起健康问题的结论。

youdao