past tense and present perfect tense

[Runs1215]

I am currently making some job applications and filling up the online application forms.

Sometimes I am asked to tell what did I learn from my internship experience, I am wondering whether I should answer with simple past tense or present perfect tense.

E.g. 1) From my previous job, I (learnt/ have learnt) how to be a good team player.
2) I (obtained/ have obtained) IT knowledge from the IT course.

Other example:
If yesterday was my birthday and it was wonderful, then I should tell my friends today that "I (had/ have had) a wonderful birthday"?

Personally I think that all the examples I give above are talking about some past events, so I would opt for the simple past tense. But it seems that I did heard someone in the past saying those in present perfect tense.

[Alan]

Hi,

The main difference is between a specific time in the past (past simple) and a time in the past that is not specified (present perfect)

Look at these two:

I lived in Switzerland in 1962

I have lived in Switzerland.

Alan
_________________
English as a Second Language
You can read my ESL story A spring in your step

[Runs1215]

Thanks a lot Alan, i got it now ^^