We use do/does or is/are as question words when we want to ask yes/no questions. We use does and is with third person singular pronouns (he, she, it) and with singular noun forms. We use do and are with other personal pronouns (you, we they) and with plural noun forms.
For the verb be, we need is or are as question words. Study this telephone conversation. You are about to meet somebody you do not know:
future: present progressive and going to
Are you older than me? ~ No, I'm not. We're the same age.
Are you taller than me? ~ No, I'm not. We're about the same height.
Is your hair shorter than mine? ~ No, it's not. It's very long and straw blonde.
Are your eyes the same colour as mine? ~ Mine are blue. What colour are yours? ~ Mine are green.
We need is or are for yes/no questions when we talk about future arrangements and plans using either the present progressive or going to future:
present tense: present progressive
Are you playing football on Sunday afternoon? ~ Yes, I am.
Are you going to train on Sunday morning? ~ Yes, I am.
Is your son coming to watch you play? ~ Yes, he is.
Is the match going to be televised? ~ No it's not, but they're going to show the highlights in the evening.
We also need is or are for yes/no questions when we use the present progressive to talk about temporary actions and developing situations in the present. Note that for a question involving the subject pronoun I the verb form am is needed:
Are you working at the moment? ~ No, not really.
Am I disturbing you? ~ No, you're not. Come in.
Are you laughing or crying? ~ Crying, mainly. This book is very sad.
Is it upsetting you? ~ Yes, it is. But I want to finish it.
When we use have to talk about habits and repeated actions and about possession, relationships and characteristics, we normally form yes/no questions with do or does:
Do you have English lessons on Saturdays? ~ We don't have any classes on Saturdays.
So do you have a lie-in on Saturdays? ~ I always have a lie-in on Saturdays.
Do you have breakfast on Saturdays? ~ I don't ever have breakfast on Saturdays. I start the day with lunch.
Does your sister have a new boyfriend? ~ Yes, she does. His name's Kevin.
Does he have a car? ~ No, he doesn't, but he has a motorbike.
Do you have a boyfriend at the moment? ~ No, I don't.
Note that when we use have got to talk about possession, we need have or has as the question word:
present tense: present simple
Has your sister's new boyfriend got a car? No he hasn't, but he's got a motorbike.
Have you got a boyfriend at the moment? ~ No, I haven't.
WWhen we are talking about things that happen regularly, we normally use the present simple tense and for this we need do or does as question words. Note that we can make negative questions with don't or doesn't:
stative or non-progressive verbs
Do you walk to school every day? ~ I usually walk to school, yes.
Doesn't your mother sometimes drive you? ~ When it's raining she does.
Do you always get there on time? Yes, I do. I'm never late.
Don't you ever oversleep? ~ No, I never do. My alarm clock wakes me up.
With stative verbs too (like believe, understand, realise, remember, like, hate, need, want, prefer) questions are formed with do or does as these verbs do not normally appear in progressive form:
Do you believe in ghosts? ~ Yes, I do.
Don't you realise it's all a load of nonsense. ~ No. I don't think it is.
Don't you understand they do not exist? ~ You're wrong. They do exist!
Do you need anything from the supermarket? ~ I'd like some coffee.
Do you prefer decaffeinated? ~ Oh yes, please try to get decaff.
Do you want me to get continental blend if they don't have decaff? ~ Oh no, don't buy continental blend. It's too strong. It keeps me awake at night.