Mix 3-1/2 cups of the flour, the sugar, salt, oil, and yeast in large bowl. Add warm water. Beat on low speed 1 minute, scraping bowl frequently. Beat on medium speed 1 minute, scraping bowl frequently. Stir in enough remaining flour, 1 cup at a time, to make dough easy to handle.

Turn dough onto lightly floured surface. Knead about 10 minutes or until smooth and elastic. Place in greased bowl and turn greased side up. Cover and let rise in warm place 45 to 50 minutes or until double. (Dough is ready if indentation remains when touched.) If you don't have a warm, draft-free place, I find it works well to place covered bowl on a rack in the oven above a pan of warm water.

Grease 2 loaf pans, 9x5x3 or 8-1/2x4-1/2x2-1/2 inches. Punch down dough and divide in half. Shape each half into loaf, place in pans. Brush loaves lightly with margarine if desired. Cover and let rise in warm place 35 to 40 minutes or until double.

Place oven rack in low position so that tops of pans will be in center of oven. Heat oven to 425 degrees F (220 degrees C). Bake 25 to 30 minutes or until loaves are deep golden brown and sound hollow when tapped; remove from pans. Brush loaves with margarine if desired. Cool on wire rack.