I was taught that the semicolon is best used to separate main clauses with contrasting ideas -- He went swimming; she did the dishes. The colon and dash, I was taught, are used to separate main clauses in which the second clause amplifies or specifies information in the first (the colon being more formal than the dash) -- He drank a lot -- he had three vodkas and eight beers. Are these "rules" still accepted and being taught, or am I an old fuddy-duddy? Also, I recently shocked someone by saying that "ain't" will eventually be accepted as acceptable English and that "Winston tastes good like a cigarette should" will become standard usage. Your comments, please. Thanks, Ed V.