It is notable that no has the rank of a two-letter word. It is vital to be able to use this word when we need to, although some of us have to practise saying it. No is more important than yes . Few words have the brevity, the clarity, the decisive ring of no. Three-letter words are also premium words.
Good examples are joy, sex, sun, sky, sea and die.
God is a three-letter word that is given added status by capitalizing the g. The special role that animals have played in our lives, both as food and as pets, is attested to by the brevity of their names - ox, cow, pig, cat, dog. Four-letter words are also strong words. This is perhaps best seen in the four-letter swear words that express our anger or disgust and which occupy such a prominent place in our informal speech. The importance of four-letter words is also illustrated by words like pain, rain, food, love, hate, walk and talk .