The word works in any situation, at any moment, unless you're not the english teacher. You can sometimes use the word twice in a sentence if the situation calls for it.
And ehh... Perhaps you can read the book when youre done perhaps.
The true more devious form of saying maybe while having some class. It still makes you a douche bag if you don't confirm your answer. Ellipses addextra confusion just to mess around.
Fred: "Hey, wanna grab some drinks tonight?"
Bill: "Perhaps..."
Fred: "Is that a yes or no though?"
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