了如指掌

Tony is very hot on local history.

托尼当地历史了如指掌。

She knows the layout of the back streets like the back of her hand.

些偏僻的街道了如指掌。

She knows physiology from beginning to end.

生理学这门学科了如指掌。

She knows every nook and cranny of the city, so she’s the perfect guide.

这个城市了如指掌，让做向道是再好不过了。