I think I understand now much better how aspect works in Klingon. I just have two last questions:

1. Is this sentence right in English?: *She had been studying from morning to evening, so the next day she passed the exam with no problem*. If it's a correct sentence, wouldn't here the ongoing action of studying be presented as a whole with a beginning and an end and as complete before the action of passing the exam? Or do you say in English *She had studied* and therefore use *-pu'*?

She had been studying from morning to evening is the past perfect progressive tense. It describes an action that is continuous from morning to evening. It implies that studying at some point prior to the time context had been ongoing. The past perfect version of this would be She had studied from morning to evening. I'm not sure if this is perfective. I don't think so — it describes the same continuous action from morning to evening. Not being progressive in English doesn't mean it can't be continuous in Klingon.

In Klingon these would both be

po ram je qubbID HaDtaH ghaH, jaj veb vaj qaD Qappu' 'ej ngeD qaD.

2. English perfect tenses which aren't progressive (e.g. *had written*, *has written*, *will have written*) are usually translated into Klingon *-pu'* or *-ta'*, right?

Usually? Not really. It depends on how they are used. Perfective is not expressed in English verbs.

Bonus question:

Sorry, I forgot to ask this at the very beginning of this thread: could *we europeans endure it* be translated as *wISIQ maH 'ewropngan* (as an apposition)?

This is a common question that we don't have a good answer to. I personally don't think so, at least not as a unit. I could imagine 'ewropngan being included parenthetically (wISIQ maH, 'ewropngan we, Europeans, endure it) but we don't have any clear instances of parenthetical splices in Klingon.

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SuStel
http://trimboli.name