Not true!

In the short story “The flying carpet” (Speak up, January 2015) I’ve noticed the verb “could” used not for general ability but for specific situations (“He could read his hand-written notes on the wall calendar”, “he could see every tiny wrinkle on the sleeping face…”). Grammars say in these cases you must use “was able to” or “managed to”. Do I have throw my grammars away? Claudio.

Yes. We’d love to know which grammar books (not “grammars”) you are using!