Conditional Sentences explanation ~~

Conditional Sentence Type 1
It descripes "what will you do" if something happens.

Form: if + simple present, future tense

Example:
If it rains, we will cancel the trip. (Kalau hujan, kita akan membatalkan perjalanan)
I will kill you if you make love with my girl friend. (Saya akan membunuh kamu jika kamu ML dengan pacar ku)

Conditional Sentence Type 2
You're not in this state now and you think what you would do if you're in this state now. However maybe you'll be in this state in the future

Form:
if + Simple Past, Conditional I (= would + Infinitive)
in other way :
if+S+V2+O, modal (past form) + V
if+S+were+O, modal (past form) + V

Remember ! "Was" is never used in conditional type 2 although the subject is he/she/it.

Example
If I were a president, I would live in a big house. (seandainya saya seorang presiden, saya akan tinggal di rumah yang besar) - (but actually you're not a president now, but maybe you'll be a president in the future)

Conditional Sentence Type 3
It is imposibble to happen because it has already happened in the past. You think about what would happened if you had done different thing in the past.

Form: if + Past Perfect (had+V3), (would + have + V3)

Example:
If I had taken the first curtain, I would have gotten a car. (kalau saja saya mengambil tirai satu, saya sudah dapat mobil)
If you hadn't gone back to the hotel to take your camera, you would have died in the WTC incident. (kalau saja kamu tidak kembali ke hotel untuk mengambil kamera, kamu sudah mati di kejadian WTC)


by : http://www.indogamers.com/f258/all_about_grammar-12501/index5.html