Answer:
A split infinitive is a common grammatical mistake that can be hard for writers to spot. Many people think they are not a big deal, but they can often have a major impact on your writing and make it hard for a reader to understand what you have to say.
Explanation:
Take, for example, this sentence:
I like to on a hot day eat a lot of ice cream.
Did you have to read it twice to be clear what it was saying? I know I did. But let's make just a little adjustment:
On a hot day, I like to eat a lot of ice cream.