I wrote a sentence which involved 故意 (gùyì; deliberately) and my teacher explained that 故意 is a negative word: you can't deliberately do something good using 故意. (I won't reproduce that sentence, since it contains other errors.)
But in English, "deliberately" ("intentionally"; "on purpose") is not necessarily a bad thing.
To help the students understand her, our teacher deliberately speaks slowly.
I might translate this to
but then we have the problem of 故意 being negative. I'm not sure if 有意 has the same issue, but it seems very similar to 故意.
Question: Is there a neutral way of saying "deliberately"?