A well-known Latin pun (perhaps the best after semper ubi sub ubi). Usually translated rhyming into the English, "I'd rather be in an apple tree than a bad boy in adversity." (I like to translate the second phrase as "than an bad man in wickedness.)
This works because Latin is a declined language, so both nouns and verbs have many forms. Sometimes the same word can be a conjugated or declined form of several different words. So:
- Malo, the first person singular present form of malo, malle, to prefer. So, "I prefer." There's an implied esse (to be) after this, making it "I prefer (myself) to be."
- Malo, the ablative of malus, an apple tree. It's in the ablative because of an implied in, so "in an apple tree." You can also translate this as "on a mast" or "inside a lemon" if that's more of your thing.
- Malo, the ablative of malus, a wicked man. It's in the ablative because it's a comparison. So, rather than using quam (than), we can just put malus in the ablative. There's another implied esse here, making this "than to be a wicked man."
- Malo, the ablative of malum, a bad deed. It's an ablative of circumstance, which is to say, "in the context of a bad deed."
Thus, you see how we arrive at "I prefer to be inside a lemon than to be a wicked man in the context of a bad deed." Which is pretty awkward. That's why we use the rhyming form, I guess.
For an English example of this phenomenon, check out Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo. For Chinese, Shíshì shishì Shi Shì, shì shi, shì shí shí shi.