Maybe a better title for this post is A Usage Error That Almost Resulted In a Usage Error. :D Anyhow, this is a true story...
I had this English teacher once who chose a very poor time to teach a lesson. For what it's worth, I was a shy kid, and I was in elementary school when this happened.
I walked up to her desk and asked, "Can I go to the bathroom?"
She looked up at me with a pleasant smile and a smidge of smugness. "No you can't, but yes you may."
I stared at her with a look of total confusion on my face. And my legs crossed.
Now mind you, I'd waited as long as I could already, so this was not the answer I'd hoped for. My whole public school rep was at stake, and she was talking in riddles.
Prodded by a worse fate than angering my teacher, I mustered the courage to ask again. "So...um...can I go to the bathroom?"
"No you can't, but yes you may."
You've got to be kidding me.
When my look of consternation turned to desperation, she relented with a roll of her eyes and a dismissive wave of her hand. "Go ahead."
It was years before I figured out what actually happened.
twisted well-intentioned educator wisdom, she was trying to get me to use the verb may instead of can, while all I wanted to do was relieve myself in a way that didn't make me the laughing stock of the entire school. If she'd taken optimal student receptiveness into consideration (which I'm sure they teach in teacher college), she would have figured out this was not a prime time for a lesson.
Out of that
scarring educational life experience came this lesson on usage.
May, might, can & could are similar, but they have different meanings and thus different rules for usage.
Can is a verb that means to be able to or have the ability to do something. May, on the other hand, means to be permitted to do something. Although can is often used and has gained acceptance, may is the correct word to use when seeking permission (May I go to to my friend's house? May I speak with you for a moment?). This is what my teacher was getting at. But, because can vs. may was (MIRACULOUSLY - my mom is also an English teacher) a usage error I was not corrected on at home, I was clueless.
Might and could are the past tense versions of may and can, and both express possibility.
I might go to the store later.
If you studied more, you could make better grades.
And for the record, though might and may are virtually interchangeable as far as meaning, might expresses less possibility of something occurring than may.
That's all for today. Thanks for visiting. :)