- Start every sentence with a capital letter.
- Always capitalise the word "I".
- End every sentence with a single appropriate punctuation mark.
- Put a space after every full stop, comma, question mark and exclamation mark.
- Do not put a space before a full stop, comma, question mark or exclamation mark.
As far as the words you have listed are concerned, note that the following are not "human sounds":
- heart pounding
- knuckle fingers
- joint cracking
Grinning makes no sound. Your heart pounding sounds noisy in your ears but is not really a sound. People choosing to crack their knuckles makes a sound but it's not a standard "human sound". "Joint cracking" is a symptom of getting old and, again, I wouldn't put it in with things like chuckling, laughing, burping etc.
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