5.I know you were only playing possum.
我知道你只是在装傻。

此语中的possum是“负鼠”，据说这种动物在遇到危险时会装死，play possum 就是“像负鼠那样装死”，与汉语的“装傻”可谓形合意切。

I know you were only playing possum. After all, it's unwise to anger the moniter. You've done right.
   我知道你只是在装傻。不管怎么说，得罪班长也很不明智。你做的对。