if 假設語氣的用法 過去假設 現在假設？？

Question

我想請問一下，if假設語氣怎樣分 與「現在事實相反」 和「過去事實相反」
例如：與過去事實相反的用法：if+過是完成式＋would+過是分詞
ex: If I had had enough money ,I would have bought a car
它為什麼不行是與現在事實相反而是與過去事實相反…
請英文好的大大幫忙解惑，謝謝！！！

Answer 1

〈1〉 事實發生的時間如果是現在的時間，也就是與現在事實相反，則假設語氣的用法如下：
If + S + V-pt (過去式)..., S + [would / should / might / could] + Vr (原形) ...
例句：If he came now, I would go with you.
但如果 if子句的動詞是be動詞的話，一律要改為過去式的were
例句：. If I were you, I would not attend the tournament.

〈2〉 事實發生的時間如果是過去的時間，也就是與過去事實相反，則假設語氣的用法如下：
If + S + had + V-pp(過去分詞)..., S + [would / should / might / could] + have + V-pp …
例句：If he had studied last night, he would have passed the exam. 　

你所舉的例句，只要在If子句後面，加上時間副詞即可成立：
If I had had enough money last year, I would have bought a car.

Answer 2

與現在事實相反的話，要用過去式(If +S.+had...,S.+would......)
與過去事實相反的話，要用過去完成式(If +S.+had+pp....,S.+would+have+pp....)

拿你的例句來說
If I had had enough money, I would have bought a car.
這是與"過去事實相反"的句子，所以會用If + S. + had+pp...,S.+would+have+pp....
在這個句子中的第一個had是動詞，第二個had是過去分詞
所以你看到這種句子的話，就可以知道它是與過去事實相反了！

如果你要與現在事實相反的句子的話，句子如下：
If I had enough money, I would buy a car.

如果還有疑問，可以再問我！^_^