Examples:

• If she were to be rich, she would be horribly obnoxious.
  It is very unlikely that she would be rich.
• If I were to have no friends, who would I spend my time with?
  Having no friends is a horrible thought.
• If Nathan were to be my boss, this job would be intolerable.
  Nathan's being my boss is a horrible concept.

Examples:

• If I were to lose my job next year, I would probably not find a new one quickly.
  Loosing my job would be terrible.
• If he were to fail his driving test tomorrow, he would have to take it again.
  He is not likely to fail his driving test.
• If Sarah were to show up late to the birthday party, it would ruin the surprise.
  Sarah will surely come on time.

Examples:

• If the fire were to have destroyed the building, it would have been a tragic cultural loss.
  The thought of such a loss is too horrible to consider.
• If the dam were to have burst, the entire town would have been destroyed.
  Such destruction is too horrible to consider.
• If Sarah were to have failed the final test, she would have lost her scholarship.
  She is an excellent student, and it is very unlikely that she would have failed the test.