present perfect/present perfect continuous

  1. How long have you been in canada? I have studied here for more than three years. 2) I have been feeling a little sick for the last week? Why has presenet perfect been used in the first example? To me, present perfect continuous is more meaningful! Why has present perfect continuous been used in the second example?
  1. The continuous tenses are not used with this particular sense of “be” (“I was in Canada”, never “I was being in Canada”). Furthermore, the present perfect continuous tense does not work properly with the verb “be” in any context. It makes “have been being”, which is horrible.

  2. There is not a vast difference between “I have been feeling a little sick” and “I have felt a little sick”. The former puts a bit more emphasis on the repeating or continuing nature of the condition. In your case, “for the last week” diminishes (or virtually eliminates) this distinction because it explains the duration.

  1. There is not a vast difference between “I have been feeling a little sick” and “I have felt a little sick”. The former puts a bit more emphasis on the repeating or continuing nature of the condition. In your case, “for the last week” diminishes (or virtually eliminates) this distinction because it explains the duration.
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    My problem is with for the last week. Although for explains the duration, last week shows the past tense. I think present perfect may be used here, but present perfect continuous is difficult to be used.

Present perfect continuous indicates continuous or repeated past action that stretches up to the present (or very recent past), so it fits sentence #2 just fine. To me, it’s more natural than the present perfect here, though the present perfect is also possible.