Manipulated

The biggest lies my parents tell are the ones I look forward to the most. "If you get such a grade for such a subject you'll get something you want or go to an event." Of course those arent the exact words but you get the point. The test comes, I get the grage they wanted yet there is no gift or on the night of the event they find the most random excuse for me not to go (example, "you didn't wash the dishes on wednesday" but there were no dishes in the sink to was on wed...) I'm still trying to find a way to get back at them but...well obviously I've had no luck with that.