I've realized that most questions begin with:

Would, should, could, etc..

What's the difference between:

Could I have some ice cream too? And

Can I have some ice cream too?

And

Would I be able to take the test again? And

Will I be able to take the test again?
could and would questions are more deferential than the corresponding can and will questions.

Ask with could and would with people you don't know very well, or with people who have a higher social standing than you, or with people you don't want to be very direct with, or with people whom you want to show respect for.

Ask with can and will with people you are very familiar with, or with people who have the same social standing as you, or with people you want to be very direct with, or in situations that don't require you to show special respect.

CJ
What common words are used to begin a question?

There doesn't seem to be a lot of them.
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PreciousJonesWhat common words are used to begin a question?There doesn't seem to be a lot of them.
Actually there are very many. "How" and the 5 familiar question words beginning with W, and their variants of which there are many, are just some of the question words in English.

a partial list... (And of course they would be capitalized when starting a question.)

is, isn't, was, wasn't, are, aren't, were, weren't, am

do, does, did, don't, didn't, doesn't

will, would, won't, wouldn't

can, can't

could, couldn't,

should, shouldn't

might, mightn't

may

shall

I'm quite sure I missed some, which others may add.
And we should not ignore the growing trend of forming a question from a statement just by changing the ending tone:

You're going?

He's not coming till Tuesday?

MacDonald's is still closed?

All in all, it is hardly worth maintaining a file of 'question words', I think.
Mister MicawberAnd we should not ignore the growing trend of forming a question from a statement just by changing the ending tone: You're going?He's not coming till Tuesday?MacDonald's is still closed?
That's of course true for oral speech. But English students are notorious for writing a declarative statement, putting a question mark at the end, and passing that off as a question.

Constructing a correct English question seems to be an area of major difficutly for students. I think the concept of question words is important; students need to know that a proper written English question almost always begins with one of those words.

Since the color function seems to rarely work, at least inside a quote, I used bold in my response.
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