take a little break =have a short rest 稍事休息；短暂休息一下。take a little取一点 。
off the top从顶部。扩展off the top of one's head意为在我头脑里最先想到的，引申为“不假思索、马上”。

【例句】
Just pass this round as I'm talking and take a little look at it.
我讲的时候大家把这个传一下，稍微看一眼。

I can't tell you the figures off the top of my head,I'll have to check it up.
我无法马上告诉你具体数字，我还得查一下。