English grammarians like to abide by ironclad rules: Don't split infinitives! Don't splice sentences together with commas! Use the active voice!
In the case of the latter, the English rule does a disservice to students of Japanese as the passive voice is used much more regularly in Japanese. So, forget this rule when studying Japanese. Use of the Japanese passive tense should be actively encouraged; it is an incredibly useful tense that can be employed to create beautifully efficient Japanese expressions.
It takes time to get used to the way the passive tense in Japanese works, and certain key phrases can help speed up the process. One that shaped my understanding is Sō iwareru to (そう言われると) and Sō iwarete mireba (そう言われてみれば). Both of them are unfinished Japanese thoughts (dependent clauses) that incorporate the passive tense of the verb iu (言う, to say).