There are very few reasons to begin a sentence with ?there are?
The next time you think your essay, article, or letter is finished, use the Search function to look for ?there.? I?ve come to suspect that, for some writers, typing There is or There are to start a sentence or clause must be an unconscious habit. I think people do not realize how often they do it–or how cluttered, unfocused, overly wordy, and weak it makes their sentences.