Some shit I found online and via Kindle. Find the error or errors:
1. Just because someone is old, doesn't mean they can't hurt you.
2. Howard Stern became Howard Stern because he flaunted authority.
3. The showdown in Eastern Europe might feel like someone else's problem as Americans face a pandemic and high inflation, and wage their own political battles.
4. She’s not sailing across the theater in a hook up, there are no pyrotechnics.
5. It was a good hike with the group and I’ll share some photos at the end of this post.
Highlight the space between the brackets for answers and explanations.
[1. No comma needed. Normally, you never put a comma between a subject and a predicate unless you're using a pair of commas to make a parenthetical expression (e.g., for appositives or whatever). In this sentence, Just because someone is old is a noun clause, i.e., that entire group of words functions as a single noun. In your mind, replace that noun clause with a simpler noun phrase like This fact. Now see what I mean: This fact doesn't mean they can't hurt you. It should be easier, now, to see why you shouldn't insert a comma. I'm also not a fan of the singular "they" in they can't hurt you. I'd rewrite the sentence this way: Just because someone is old doesn't mean she can't hurt you. Note that the singular "they" is nowadays considered acceptable in most types of writing except, perhaps, for very formal registers.
2. Diction: the word is flouted, not flaunted. To flout the law is to show contempt for the law, usually in an obvious, open, unabashed way. To flaunt your new jewels means you're brazenly showing them off to everyone around you. There is, however, some debate on this point: there are experts who argue that flaunt the law can indeed refer to a defiant show of disdain for the law. So consider this correction to be in line with my sometimes-curmudgeonly, old-school worldview. Some experts will push back against what I'm saying here.
3. Delete the comma. This is a compound predicate, so no comma is needed. Sheila sat down and farted. Never: Sheila sat down, and farted. In the above sentence, the compound predicate is face... and wage...
4. One problem is the term hook-up, which should be hyphenated or written as a closed compound: hookup. The other problem is the comma, which should be a semicolon (this is called a comma splice—an error in which you're using a comma when you really ought to use a semicolon). A semicolon separates two independent clauses, which is what you've got here.
5. Sorry, John, but you're a rich source for punctuation errors. I could do a whole textbook using your sentences as examples! Anyway, there ought to be a comma before and. The comma-and locution works like a semicolon, separating two independent clauses, which is what you've got here, too. Don't make the mistake of applying this rule to complex sentences, which have subordinate (dependent) clauses and follow their own rules.]