open-and-shut

形容词 open-and-shut:

1. so obvious as to be easily solved or decided

1. As far as I can see the whole matter is open-and-shut.
   我看整件事是一清二楚。
2. He's obviously guilty it's an open-and-shut case.
   他显然有罪--此案昭然若揭。

o.pen-and-shut

adj.（形容词）
So obvious as to present no difficulties; easily settled or determined:
一目了然的：十分清晰以至于不会带来任何困难的；容易解决或作出决定的：
例句：
an open-and-shut case.
一目了然的案件