If he had left the party earlier, he wouldn't have cycled in the dark without lights.
If there had been a lot of traffic, he wouldn't have cycled in the dark.
The driver might have seen him, if he hadn't driven fast.
If the driver hadn't taken Francis to hospital, he would have died.
If Katy hadn't felt guilty, she wouldn't have visited him.
If подл + had + глагол 3 столбик или - ed, подл would/might + have + глагол 3 ст или - ed