And when someone says your words or actions hit the nail on the head, he means what you said or did was exactly right.

VOA: special.2009.09.20

And to give you a size perspective, that is about the size of my pinky finger nail, 4 mm on the side.

这个芯片，有我的手指甲那么大，边长4毫米。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

Then they nail on battens to hold the hatch coverings firmly in place.

VOA: special.2011.03.06

Lenore answered, "It is as big as the nail on my finger.

VOA: special.2009.03.28

With seconds left in regulation time, South Africa equalized on a free kick by Mphela that sent the game into 30 nail-biting minutes of overtime.

VOA: standard.2009.06.29