Teorija

FORMULA
 +/ - / ?
am/ is / are + Ving
 
FORM
Affirmative sentences: am/is/are + Ving 
IamVing I am working
WeareVing We are working
YouareVing You are working
TheyareVing They are working
HeisVing He is working
SheisVing She is working
ItisVing It is working
Negative sentences: am/is/are + not + Ving 
IamnotVing I amnot working
WearenotVing We are not working
YouarenotVing You are not working
TheyarenotVing They are not working
HeisnotVing He is not working
SheisnotVing She is not working
ItisnotVing It is not working
I am not = I'm not (not: I amn't !)
are not = aren't
is not = isn't
Interrogative sentences: ... am/is/are + S + Ving … ?
(QW)am/is/are SVing(what/where/when)?
 AmI working ?
 Areweworking ?
Whereareyouworking now?
 Aretheyworking at the moment?
 Isheworking ?
Whyissheworking this week?
 Isitworking ?
Short answers:
 
Yes, S + am / is / are. 
No, S + isn't/aren't. (No, I'm not.)
Yes,Iam.   No,I'mnot.
Yes,weare. No,wearen't.
Yes,youare. No,youaren't.
Yes,theyare. No,theyaren't.
Yes,heis. No,heisn't.
Yes,sheis. No,sheisn't.
Yes,itis. No,it
isn't.
Note: In short answers we use pronouns (I, we, you, they, he, she, it)
- Is Mary working this week?
- No, she isn't.
(Not: No, Mary isn't.) 
***
V - verb (the infinitive without "to")
S - subject
QW - question word