1) Susan would have managed to brake in time if she hadn't been driving too fast. FUTURE PERFECT IN THE PAST + IF + PAST PERFECT CONTINUOUS 2) But for your help, I would certainly have failed the placement exam. BUT FOR + (PRONOUN) + NOUN + COMMA + FUTURE PERFECT IN THE PAST 3) If Susan hadn't fallen ill, Adam would have visited us. IF + PAST PERFECT + COMMA + FUTURE PERFECT IN THE PAST 4) Had she had any money on her, she would have taken a taxi. INVERSION + PAST PERFECT + COMMA + FUTURE PERFECT IN THE PAST (IF SHE HAD HAD = HAD SHE HAD) 5) If we hadn't forgotten to take a map, we wouldn't have got lost in the mountains. IF + PAST PERFECT + COMMA + FUTURE PERFECT IN THE PAST 6) If I had had enough money, I could have gone to the cinema. IF + PAST PERFECT + COMMA + MODAL VERB + HAVE + PAST PARTICIPLE
Explanation
Third Conditional is used to talk about 'imaginary' situation contrary to facts in the past. It is also used to express criticism or regrets. If I had met John yesterday, I would have given him the CD. IF + PAST PERFECT + COMMA + FUTURE PERFECT IN THE PAST I would have missed my bus if I hadn't taken a taxi to get to the bus station. FUTURE PERFECT IN THE PAST + IF + PAST PERFECT
We can use BUT FOR + NOUN to say that one situation is depending on another situation. But for Sarah's hospitality, I wouldn't have felt so well in their house. BUT FOR + (PRONOUN) + NOUN + COMMA + FUTURE PERFECT IN THE PAST
Using inversion, we can omit IF placing HAD before the subject. Had she told me about her problems, this disaster would never have happened. INVERSION + PAST PERFECT + COMMA + FUTURE PERFECT IN THE PAST (IF SHE HAD TOLD = HAD SHE TOLD)