1. If you accidentally say There is and want to use a plural after, (for example, a lot), you can just say a number in between. The sentence stays correct, you just have to say 2 additional words. I personally never had this problem

2. This is internet. You are free to edit your comment and reread it a million times before posting

Hope you understand what I'm trying to say, not being native sometimes restricts my ability to properly articulate semi-complex stuff