Beware of Negatives
Start with a negative at your peril! You may be writing something you didn't mean at all.
Look at this sentence:
I didn’t pay her a compliment because she is my sister.
Does this mean that you didn’t pay a compliment to your sister, or that you did pay her a compliment but for a reason other than your relationship with her?
Misunderstandings of this kind are common when sentences begin with a negative statement. This thought provoking one is attributed to a writer and comedian called Alan Whitney Brown.
I am not a vegetarian because ... (you are probably expecting something about it being natural to eat animals or that you would miss a juicy steak too much). In fact you get this elegant reversal:
I am not a vegetarian because I love animals; I am a vegetarian because I hate plants.
Beware of negatives – or enjoy their possibilities – but whatever you do, make sure your meaning is clear when you need it to be.