Most people learn about the “be” verb and how to use “there is” and “there are” from the very beginning of their English studies, but more and more you will hear native English speakers using these very basic structures incorrectly.

While “there is” should be followed by a singular noun and “there are” should be followed by a plural noun, people are increasingly using “there is” in all cases for one simple reason - it’s easier and better sounding to use the contraction “there’s” than “there’re” when speaking! 

So, you may hear sentences like “there’s a lot of people” or “there’s some leftovers in the fridge” even though they are grammatically incorrect. This mistake has become so common that I have even seen it in newspaper headlines and heard it frequently in news reports. 

So, should you try to imitate this natural speech pattern? In general, I would say no. I don’t think it’s necessary to intentionally make grammatical mistakes in order to sound more natural, but if you spend a lot of time around people who speak like this, you may start to do it in casual conversation, too, and that’s fine.