It's a piece of cake 小菜一碟

例句：

Never say die,it's a piece of cake.

不要放弃，它就是小菜一碟。

I guess it's a piece of cake for you.

我想这对你来说就是小菜一碟。

A:I can't believe you solve this math problem in 30 seconds.

B:Well,It's a piece of cake.

背景音乐：

I got it-Jack Johnson