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Do you agree with the explanations to this question and statements?
Judy: How long have you been in Canada?
Claude: I have been studying here for more than three years.
OR I have studied here for more than three years.
Depending on where the two friends meet in Canada or in another country, the question can imply that Claude is or is not in Canada at the moment.
The first answer implies that Claude is still in Canada or was recently in Canada. (Maybe to suggest that he was in Canada recently it would be better to use ‘there’. I think ‘here’ suggests that the person is still in Canada.)
The second answer implies that the person is not in Canada any more. The action is complete.