Sorry Jeff but you are incorrect re usage of the phrase. "How many children have you." It is in fact quite common to hear something like "So, how many children have you?" "How many children have you?" How many kids have you? "How many cats have you?" "How many days off have you?" and so on and on... Very everyday questions and a very natural usage of our english language, (though not grammatically Cambridge British.) It's still used A LOT and you'd fit right in if you naturally use it... though l DO sometimes use "do you have?" I dont' think about it l just know when l want to be/ sound "more correct." But These phrases are used by various nationalities of speakers of english and nobody would 'bat an eye' it's common usage and if you know better and correct them, l think they'd be shocked/ surprised/ or laugh at you for thinking such a thing. I t's grammatically incorrect but the majority don't know, and couldn't care less. Just be sure and learn to be grammatically correct especially if taking Cambridge exams. After that just have fun and become almost or as fluent or even better than us mere mother tongue everyday natural english speaking mortals. Funny thing is
As this course is open to English English speakers, who would be unlikely to use 'how many children does he have?' and would say 'How many children has he?' it seems to me that it is about time you made the English English an acceptable answer. After all, this was brought up at least 7 years ago.
I am irritated by being obliged to use an American expression that I would not use at any other time. Please make this an acceptable answer.