Cord vs. Chord
Wrong: Something in what she said struck a cord.
Right: Something in what she said struck a chord.
Cord has many meanings, but most relate to string, wire, a cord-like structure (e.g., spinal cord), or binding of some sort (the cords of marriage). Chord can mean a combination of musical notes or, in this case, evoking a feeling or emotion.
Funner vs. More fun
Wrong: I think tennis is a lot funner than bowling.
Right: I think tennis is a lot more fun than bowling.
I’m sure funner is used tongue-in-cheek sometimes; but it’s not a proper word, falling into the same category as ain’t. It should only be used in dialog where the speaker is supposed to sound uneducated. If you use it in narrative, you’ll be the one sounding uneducated.
There are still more to come.