Being one myself, I know well that there are many sentences that we high school Latin scholars are amused by. Here's a sampling:

"Semper ubi sub ubi"

This one takes a little explaining. "Semper" (as in Semper Fi, "Always Faithful") translates to "always". "Ubi" translates to "where", as in "Where he lives". "Sub" then translates to "under"
Thus: Always Where Under Where
or: Always wear underwear.

See also: Carpe Apenodytes - Seize the Penguins
Also: Any sentence containing the *Latin* word "cum" (meaning with or when) is sure to cause the more immature of us to giggle a little.