在書上看到第二次了，感覺滿重要的。
If引導的副詞子句中，若有were、should或過去完成式助動詞 had出現時，都可以將were、should、had置於主詞之前，省略原有的 if。
例如:
If it were not for you, I wouldn't do it.
Were it not for you, I wouldn't do it.
若不是因為你，我才不會去做呢。
If Paul were here, I would tell him the truth.
Were Paul here, I would tell him the truth.
如果Paul在這裡，我將會告訴他真相。
