There are only two real rules: answer the prompt and don't be boring. If contractions work then go for it. This isn't an academic paper or one that would otherwise require such formality.
I watched 'The Paper Chase' yesterday... I'm glad that there are people honest enough to say, "Chill the ___ DOWN!" when a friendly reminder is needed. Thanks Nicole! : )
@runiggyrun Thank you for your explanation! I actually drew it out on a piece of paper. One question I have is why doesn't the "must be true" bucket and "must be false" bucket encompass the "could be true" bucket and "could be false" bucket?
... telling me that THEIR recycled paper has the same brightness, ... market, he states "recycled paper is not necessarily of worse ... the beginning" the finest paper was made from recycled material ... to buy YOUR contemporary recycled paper!
The other answers ...