How would you see ia a sentence had comma splice?

You would see a comma splice in a sentence when two independent clauses are joined together only by a comma, without a coordinating conjunction (and, but, or, nor, for, so, yet) or a semicolon.

Here's an example:

Incorrect: The cat chased the mouse, it ran under the couch.

Correct: The cat chased the mouse, and it ran under the couch.

Or:

Correct: The cat chased the mouse; it ran under the couch.