sentences:  There are words which appear on the surface to mean exactly the same thing but which, in fact, have slightly different shades of meaning and must be chosen appropriately if a speaker wants to convey precisely the message intended.It is generally stated that English has around 170,000 words, or 220,000 if obsolete words are counted; this estimate is based on the last full edition of the "Oxford English Dictionary" from 1989.Over half of these words are nouns, a quarter adjectives, and a seventh verbs.