What is the purpose of a map’s key?
to tell what part of the world it shows
to show the directions
to give demographic information
to you decipher symbols and scale

a phrase is a set of word that make a sense, an expression formed by two or more words.

" teacher´s dictum on the possession of human "

" made a pile practicing "

" lived to an impressive age and dies "

a clause, in a grammar way is a series of words that have a complete meaning.

" was irritated by the persecution of those who called themselves "

ccd puts the honeybee populations and crop health at risk.

the above detail from paragraph 2 supports the inference about honeybee.