I've been trying to explain to a non-native English speaker why "We could lift the rock" allows two interpretations:
- "We were able to lift the rock"
- "We might be able to lift the rock [in the future]"
but "We could get caught" only allows one:
- "We might get caught [in the future]"
I realize that one would need to say "We could have gotten caught" if one meant "There was a possibility that we would be caught". However, I can't put my finger on what makes the instances different. Is it the use of the passive? Is it the semantics?
UPDATE: I understand that one can add more context that makes the "past" interpretation acceptable: "He thought that we could get caught." My question is: in the absence of such additional context, why is "We could lift the rock" ambiguous while "We could get caught" is not?