"My teacher said never to start a sentence with because."
"A sentence is a complete thought." (Define complete, I would tell them, which they couldn't.)
My favourites always had to do with punctuation, such as:
"Use a comma whenever you take a breath in reading a sentence." (To which I would ask: "What if you had just run up stairs? What if you had a cold?")
"Always introduce a list with a colon."
"Use semi-colons to separate items in a list after a colon."
Punctuation is a minefield. That is something we can all agree on as the rules continue to confound the unwary writer. Take a look:
|Commas and hyphens gone wild!|
Okay, this is nitpicking perhaps, since the meaning is very clear, but without a comma after later (blue circle), this sentence suggests that a decade took place in the latter part of 1851. Without a time dilation device, this would be impossible. Add a comma and the reader no longer needs a working knowledge of the space-time continuum:
Matthew Bell married Isabella Humble in 1840 and just over a decade later, in 1851, they moved...
But there's another comma problem in this paragraph as well (second blue circle). The writer wants to add information about the city of Guelph: at the time of the Bells' settlement, the city was 24 years old. The modifying clause beginning with which needs to be enclosed by commas to set it apart. But the writer added an unnecessary and confusing comma smack in the middle of the clause:
...Guelph, which was at the time, only a 24 year-old settlement. (I'll deal with that hyphen in a moment.)
Remove that comma after time! It's not required - in fact, it complicates the meaning by suggesting Guelph simply "was at the time" - or, in other words, Guelph was, as opposed to not being in existence. That comma removes the connection of Guelph to its 24 years and leaves it simply as "Guelph was." Complicated, subtle - wrong! Here is the correction:
...Guelph, which was at the time only a 24-year-old settlement.
There were not 24 Guelphs, each one a year old (yellow circle). There was one Guelph, and it was 24 years old. If you turn that age description into an adjective preceding the noun settlement, you need to add hyphens. Not just one hyphen, but two - enough to turn the age description into a single adjective: ...24-year-old...
Punctuation has the power to obscure - or facilitate - meaning. But you have to put it in the right place.