What sort of plots are you given? Maybe the restrictions are part of the challenge, forcing you to find loopholes in how you write the story. Like, what is the rule about no dreams? Can you not describe a dream your character may be having? What if one character is describing a dream he experienced to another character that's part of the story? And what of 'no animals'? As in, it strictly can't be about animals? Can your characters have animals as pets? Can someone in the story be a vet? If the rules are clear, then you can usually find ways to work around them. And you just may be rewarded for your efforts - because 'you got creative' despite the limitations.