yes, I do. For example : I had finished cleaning the room when he came in.
Quite. Actually my message was code for: If we knew your native language, or the language you know best, many of us would be more confident in answering your questions, since such knowledge often gives a teacher an idea about why you are asking, and why it is you are having trouble with a certain concept.
Many of the teachers here are bilingual, at least to some extent. Others have a good idea how the various L1s contribute to specific misunderstandings in English.
Anyhow, this message is not specific to you; it applies to all members who decide not to reveal their first language. That is your right, of course. There may be good reasons why you don't want us to know. But it is very useful information for some teachers.
By the way, the example you gave was in English, so it's not really an example of the past perfect in your native language, unless your native language is English. (Not that I actually asked for an example).