Most of the time, my headache is caused by the lack of 語感 （anther question, is there a word in English for 語感？）， both with grammar and vocabulary.
As for the present perfect tense, the examples I found that may fit my situation all come with an adverb clause that indicates a duration. The following explanation is from http://www.englishpage.com/verbpage/presentperfect.html.
USE 2 Duration From the Past Until Now (Non-Continuous Verbs)
With Non-Continuous Verbs and non-continuous uses of Mixed Verbs, we use the Present Perfect to show that something started in the past and has continued up until now. "For five minutes," "for two weeks," and "since Tuesday" are all durations which can be used with the Present Perfect.
Examples:
- I have had a cold for two weeks.
- She has been in England for six months.
- Mary has loved chocolate since she was a little girl.
Although the above use of Present Perfect is normally limited to Non-Continuous Verbs and non-continuous uses of Mixed Verbs, the words "live," "work," "teach," and "study" are sometimes used in this way even though they are NOT Non-Continuous Verbs.
