Commas. Such a tiny piece of punctuation, so wrongly used so much of the time.
There’s one simple word which will always help when pondering whether to add a comma or not:
DON’T
Almost always, commas are inserted where they aren’t needed. Two examples:
ONE
For their sixth birthday recently, and as part of the farm’s petting zoo schedule, worker Joan Bloggs, treated the pigs to an extra helping of slop.
TWO
Back home, for the past year, Smith has been training the two rhinos to become more accustomed to people to make interaction easier and allow vets to check them.
In the first example, the comma before the word treated is unnecessary. In the second example, the oddness of the phrase “for past year” is not helped by dotting commas around. Rather rewrite them both:
As part of the farm’s petting zoo schedule, worker Joan Bloggs treated the pigs to an extra helping of slop for their sixth birthday.
Smith has spent the past year training the two rhinos to become more accustomed to people to make interaction easier and allow vets to check them.
SIMPLE RULE OF THUMB:
Imagine yourself speaking the sentence. If there’s a place where you would take a breath (like here), you could tentatively consider inserting a comma.
