In the third form, if the condition is true, then the first set of commands is performed. If the condition is false, and if the second condition is true, then the second set of commands is performed.
Roast your pork shoulder in the oven at 350 degrees F for 30 to 35 minutes per pound for a nice slicing roast. At this temperature, a 6-pound pork shoulder will require 3 to 3 1/2 hours to roast. Check for doneness by placing a meat thermometer into the roast at the thickest point. Be careful not to touch the bone.
To bake a frozen pork roast, preheat the oven to 350 F, and place your roast in a shallow pan in the center of the oven. For a larger, thicker, tougher cut, such as a pork shoulder, cook uncovered for around 45 minutes per pound.