Now let's review and practice a bit.
Remember the third conditionals are used to describe a past event that is different to what really happened.
Now read the following sentences and Mark second conditionals as C and third conditionals as T.S. is.
I'd known I wouldn't have done X
third conditional.
They wouldn't have missed the bus if they had left earlier
third conditional.
If Sam had more free time he would be happier
second conditional also remember the third conditionals are solely hypothetical.
Thus there is always some implication of regret.
Now rewrite the following sentences so that their meanings stays the same.
I could call Kelly that time.
I know that she would help me
if I had called Kelly.
She would have helped me
I really wanted to go to the party but I had too much homework
if I had finished my homework I would have gone to the party.