Why did you do that, you cretin?

你为什么做那事, 你这个笨蛋?

Why else would I have chosen such a disreputable looking cretin?

为什么我选中的其他人象个白痴?

What you do is pointless. You can be replaced from one day to the next by any cretin sitting next to you.

你所做的任何努力都是无意义的，说不定哪一天你就会被你身边的白痴所替代。