Here are the correct versions of the paragraphs you worked with in the proofreading exercise on page one. For more information about the confusables in these paragraphs, follow the links to items in our Glossary of Usage: Index of Commonly Confused Words.

• Cows
  To my mind, the only possible pet is a cow. Cows love you. They are harmless, they look nice, they don't need a box to crap in, they keep the grass down, and they are so trusting and stupid that you can't help but lose your heart to them. Where I live in Yorkshire, there's a herd of cows down the lane. You can stand by the wall any hour of the day or night, and after a minute the cows will all waddle over and stand with you, much too stupid to know what to do next, but happy just to be with you. They will listen to your problems and never ask a thing in return. They will be your friends forever. And when you get tired of them, you can kill them and eat them. Perfect.
  (Bill Bryson, Neither Here Nor There: Travels in Europe. William Morrow, 1992)

• How to Build a Fire in a Fireplace
  Though "experts" differ as to the best technique to follow when building a fire, one generally accepted method consists of first laying a generous amount of crumpled newspaper on the hearth between the andirons. Kindling wood is then spread generously over this layer of newspaper and one of the thickest logs is placed across the back of the andirons. This should be as close to the back of the fireplace as possible, but not quite touching it. A second log is then placed an inch or so in front of this, and a few additional sticks of kindling are laid across these two. A third log is then placed on top to form a sort of pyramid with air space between all logs so that flames can lick freely up between them.
  (Bernard Gladstone, The New York Times Complete Manual of Home Repair. Macmillan, 1971)

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