Grammar

Those sentences won't work as written. You can say he could have passed the exam yesterday or they could have escaped from the prison last night.

Can you give me some examples to show how we can use "could" with past ability?
kind regards

George was famous for his strength. He could straighten horseshoes with his bare hands.
Some of the older people could remember the days when goods were shipped up and down the river on barges.
She was fascinated by the nineteenth century, and could tell you anything you wanted to know about Queen Victoria.

Thank you Blue Jay, so according to your answer we can use "could"for general situations not specific situations for past tense. Otherwise we have to use "was able to" or "were able to". Am I right?
kind regards

In any of my example sentences was/were able to are possible in place of could.
Generally we use could have for a specific situation and could for a general one.
Fred could fix cars and tractors—in fact he could fix just about any kind of machine.
Fred could have fixed your car if you'd

Thank you so much for your useful answer.

Joseph AOtherwise we have to use "was able to" or "were able to".

Yes. You can't use "could" to express success.
.
We could catch the bus does not mean we succeeded in catching the bus.
We were able to catch the bus means we succeeded in catching the bus.
.

CalifJim "We could catch the bus". You said this sentence doesn't mean we succeeded in catching the bus. What does mean, please?

Kind regards

Can I use "the mechanic" instead of "Fred"? as follow:

-The mechanic could fix cars and tractors.

Best regards

Joseph AQuote Can I use "the mechanic" instead of "Fred"? as follow:-The mechanic could fix cars and tractors.

Yes.