I've had trouble with active and passive voice, "Engineers designed the cars" active, "The cars were designed by engineers" passive. From what I've read about it, in creative writing you should generally avoid passive. But is it okay to use it sometimes? I was writing and came across this sentence: A flutter rose inside her upon seeing him, but the tickle was soured by the acrid emotions churning in the pit of her stomach. The first part is an active statement, but the second is passive, right? "The emotion soured the tickle", that would be active structure as opposed to "The tickle was soured by the emotion" ... but I find that it sounds better, to me, anyway, with the passive form. Is that wrong, something an agent or editor would frown upon? Or is it okay in some circumstances, such as this? OR am I completely wrong on my understanding of this concept... That's always possible. Thanks!
Occasionally using passive voice is completely okay. As you've pointed out, it sometimes reads better or is necessary to give the feel/focus you want. No agent/editor would reject you for occasional use of passive voice.
Concur with @Tenderiser . I will use passive if the recipient of the action is more important than the active agent, or the active agent is anonymous or unknown. In your example "The agile, fast cars were designed by engineers." The car and its characteristics are important, and of course they were designed by anonymous engineers, as are all cars. "The best engineers in the world designed the cars to be agile and fast" The engineers are important, the cars just the recipient of the design action. And in general, I keep it to the minimum.
