Can vs Could usage differences
He goes to London every month so that he can see his ailing father.
He goes to London every month so that he could see his ailing father.
Which of the above sentences is correct??
My friends are saying second sentence is wrong, as “goes to london” is present tense form and “could” is used for past tense forms. So we can’t use “could” here.
But I learnt could is also used for hypothetical forms also. Why can’t we use “could” here in hypothetical sense or to show possibility? For example: He goes to London every week so that he could see his ailing father (If hospital authorities permitted him or if he wanted to )
But I learnt could is also used for hypothetical forms also. Why can’t we use “could” here in hypothetical sense or to show possibility?
Because when you said "he goes to London" you expressed it as a definite action, not a hypothetical.
You could say,
He goes to London every month, so he could see his father (if he wanted to).
(By removing the that we make seeing the father a hypothetical consequence of going to London, rather than the reason for going to London)
or,
If he took a day off work, he could go to London so that he could see his father.
(making going to London a hypothetical and thus seeing the father also becomes hypothetical)