Teorija

FORMULA
 + - / ?
 V/Vs do/does + V
  
FORM
Affirmative sentences: V/Vs
IVI work
WeVWe work
YouVYou work
TheyThey work
HeVsHe works
SheVsShe works
ItVsIt works
Negative sentences: do/does + not + V
Idon't + VI don't work
Wedon't + VWe don't work
Youdon't + VYou don't work
Theydon't + V They don't work
Hedoesn't + VHe doesn't work
Shedoesn't + VShe doesn't work
Itdoesn't + VIt doesn't work
do not = don't
does not = doesn't
Interrogative sentences: ... do/does + S + V … ?
(QW)do/ does
S
V
"extra information"?
 DoI workon Sundays?
 Doweworkat weekends?
Wheredoyouwork ?
Whendotheywork ?
 Does heworkin London?
Whydoessheworkevery day?
 Does itwork ?
Short answers:
 
Yes, S + do/does. 
No, S + don't/doesn't. 
Yes,Ido.   No,Idon't.
Yes,wedo. No,wedon't.
Yes,youdo. No,youdon't.
Yes,theydo. No,theydon't.
Yes,hedoes. No,hedoesn't.
Yes,shedoes. No,shedoesn't.
Yes,itdoes. No,itdoesn't.
Note: In short answers we use pronouns (I, we, you, they, he, she, it).
— Does Mary go shopping every day?
— No, she doesn't.
(Not: No, Mary doesn't.)
Revise!
The verb "be" in Present Simple.
The verb "have" in Present Simple.
  
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S — Subject of the sentence
QW — Question word
V — Verb (the infinitive of the verb without "to"/ Present Simple verb (for I, we, you, they). E.g. write, go, listen, etc.
Vs — Present Simple verb (for he, she, it). E.g. writes, goes, listens, etc. Revise how to add "s" to a verb here.