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“The play may begin at any moment,” I said.
“It may have begun already,” Susan answered.
I hurried to the ticket office. “May I have two tickets please?” I asked.
“I’m sorry, we’ve sold out,” the girl said.
“What a pity!” Susan exclaimed.
Just then, a man hurried to the ticket office.
“Can I return these two tickets?” he asked.
“Certainly” the girl said.
I went back to the ticket office at once.
“Could I have those two tickets please?” I asked.
“Certainly,” the girl said, “ but they’re for next Wednesday’s performance. Do you still want them?”
“I might as well have them,” I said sadly.
They can be used to request permission.
Can is usual among friends and equals;
Could and may are both common “polite” forms;
Might suggests hesitation, trying to be very polite (as to one’s superior)
May I ask you a question?
Can I help you?
