Mr. King is a person's name, which makes it a proper noun. Proper nouns are always capitalized.
mister
'Mr' is part of a name or designation, for example 'Mr Brown' or 'Mr Speaker'. It therefore forms part of a noun phrase.
The word Mr is an abbreviation. It is an abbreviation of the word mister.
Joseph is a noun. The title Mr is usually considered part of the name.
The speech took place at the 1963 Washington D.C. Civil Rights March
Lionel Logue, played by Geoffrey Chaucer, is the King's speech therapist in the Hollywood film The King's Speech. The Queen calls him Mr. Logue or Lionel.
King is usually a noun. In checkers, though, it can be a verb as in "king me", meaning crown me king.
mister
a great big gorilla
Takes is a verb in that sentence.
It is very important to understand the great speech given my Martin Luther King Jr. The last part of his speech, he has a dream that freedom will ring, that people of every color will be able to hold hands peacefully.
Slang