Sentences which begin with “there” followed by a form of the verb “to be” put the subject after the verb. Most sentences, like the one you are reading now, name the subject first, and then tell what the subject does. But when the sentence begins with “There is” or “There was” the subject is the third or fourth word, a weaker construction than the typical subject-verb construction.
“There is” and “there were” compound the weakness by using the weakest verb in the English language, “to be.” In a sentence like “There are two dogs,” we know nothing about the dogs except that they exist. Even if we add a bit more information, such as “There are two dogs across the street,” we know little except that they exist across the street.
“There” like “It” (It’s raining out. It’s three o’clock) is a filler word, a word to get the sentence going without adding any information. This construction is similar to a child starting a paragraph with, “I’m going to tell you about my pet dog.” This child’s sentence offers a way for the child to start, but a poor way. If the sentences which follow are about a dog, do you really need to start off by saying that you are going to tell us about your dog?
Sometimes the noun that follows “There is” is a noun which can be changed into a verb. When the sentence is rewritten, the sentence becomes more dynamic. For example, take the sentence, “There was anger in the school about the school lunches. “Anger” has no verb form, but “fume” or “seethe” are synonyms which could be used as the desired verb. But now we have another problem. Who fumes? Who seethes about the lunches?
This problem leads to another shortcoming of “there is.” Many times “there is” creates a passive construction, one in which the reader doesn’t know who is acting. Most of the time, the writer isn’t intentionally hiding who is doing the action in a sentence. The writer is rather relying on an easy way to begin a sentence. Why not come right out and say the actor, making the sentence more direct?
Another reason not to start a sentence with “There is” is that the beginnings of sentences receive the most focus. English speakers are accustomed to hearing the doer of the action named first. (“John bounced the ball” not “The ball was bounced by John.”) But when the beginning is a filler word like “There,” that opportunity to highlight the subject is squandered. We focus on a meaningless word.
Analyze a piece of your own writing. Circle all the “there is” and “there are” constructions whether they occur as the first words of sentences or the first words of subordinate clauses. Now figure out how to eliminate them.
One exception: When you write dialog, write the way people speak. People say “there was” and “there will be” habitually. On the other hand, if you want your speakers to sound dynamic, active, animated or enthusiastic, don’t put the words “there is” into their mouths.