Frankly speaking, drawing is not a piece of cake to me.
说实话，学画画也不是件轻松的事。
It's known that a knowledge of many languages is not a piece of cake.
众所周知，通晓多门语言不是件容易的事。
To start an undertaking is not "a piece of cake".
创业不是一件容易的事情。
To get your own happiness is only a piece of cake. If you are not happy now, then think about what I said. There must be something wrong with you.
得到你自己的幸福没什么难的，如果你现在觉得并不高兴，那么想想我所说的，肯定有哪里出了问题。
When you want a piece of chocolate cake, you can have one, just not every night.
当您想要一块巧克力蛋糕，你可以有一个，就不是每个晚上。
When you want a piece of chocolate cake, you can have one, just not every night.
当您想要一块巧克力蛋糕，你可以有一个，就不是每个晚上。
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