What do foreign learners find difficult about English? Part 2

Questions
One the earliest and most basic things you need to be able to do in a language is to ask a question. Otherwise you can't get what you want. In French you can add est-ce que to the front of the statement. In Japanese you simply add the particle -ka on to the end of the last word in the sentence. There – you have instantly learned how to ask a question in Japanese.
It's not so easy in English. Questions are hellish for a beginner.
It all starts off quite easily with the subject-verb swap common in Western European languages:
She is Irish > Is she Irish?(words that change position are underlined)
But that only works for certain verb such as be, can, could, will, would.
It gets a bit more complicated with multi-part verbs. You have to make sure you do the swap with right part:
She is working in London > Is she working in London?
She has been working in London. > Has she been working in London?
So far, not bad. But applying the same rules:
She works in London. > Works she in London? No, we (in contemporary English) have to say: DOES she work in London?
So how would you explain the rules that creates this transformation (rules, by the way, that you faultlessly follow every day)?
She works in London > DOES she work in London? (Words that change form are in bold; words added in CAPITALS)

Here are the rules:

1. Take the verb do
2. Look at the tense of the main verb (works) and put do in the same tense > do
3. Make it agree with the subject (she)> does
4. Place it before the subject > does she
5. Take the main verb (works) and change it to the base form >work
   

The person you're asking has left the building.

Similarly in the past tense:
She worked in London. > DID she work in London?

Not only that, but the form of the question can depend on what missing information is being asked for:
Sarah gave the tickets to Steve. > WHO gave the tickets to Steve?
But we can't (in a genuine question, rather than for showing surprise) do the parallel expression: Sarah gave the tickets to WHO? We have to say: WHO DID Sarah give the tickets to?
(And that's before we even consider when it is 'correct' to use whom...)

Another difficulty is how many words to move to the front.
She works in London three times a week. > How many does she work times a week? NO
>How many times does she work in London? NO
>How many times a week in London does she work? NO
>HOW MANY times a week DOES she work in London? CORRECT!

I hasten to add that this is not how I teach questions to my students - I have tried to give the learner's-eye view and emphasise the bewildering aspect of question formation. If you go 'one level up' there are actually quite simple and beautifully precise rules that enable us to generate questions. The problem for the learner is that they have to have quite an advanced knowledge of English syntax to be able to get a clear view of it all.
It's a lot to ask for, when you want something.