The standard four food groups are based on American agricultural lobbies. Why do we have a milk group? Because we have a National Dairy Council. Why do we have a meat group? Because we have an extremely powerful meat lobby.
The most common type of meter in English poetry, in which there are five iambs (unstressed then stressed syllable pair) to a line: "But soft!/ What light/ through yon/der win/dow breaks?" (Romeo and Juliet).