Theorie:

Formation of present continuous:
  
Structure
  
Positivebe + verb + ingHe is working today.
Negativebe + not + verb + ingHe is not (isn't) working today.
Questions
be + subject + verb + ing
 
question word + be + subject + verb + ing
Is he working today?
 
Where is he working today?
 
Verb 'to be': long forms and short forms
 
AffirmativeI am – I'm
he is – he's
she is – she's
it is – it's
we are – we're
they are – they're
you are – you're
NegativeI am not – I'm not
he is not – he isn't / he's not
she is not – she isn't / she's not
it is not – it isn't / it's not
we are not – we aren't / we're not
they are not – they aren't / they're not
you are not – you aren't / you're not
 
Formation of the present participle (often called 'the -ing' or 'continuous form')
 
 adding -ing to the bare infinitive:work – working
Consonant after a short, stressed vowel at the end of the word
 
If the consonant is not stressed
double the consonant:
 
do not double it:
sit – sitting
  
benefit – benefiting
In British Englishdouble one -l at the end of the word:travel – travelling
One -e at the end of the word
 
Double -e
leave out the -e:
 
add -ing:
write – writing
  
see – seeing
Verbs ending in -iechange 'ie' to 'y':lie – lying
Verbs ending in -cchange 'c' to 'ck':picnic – picnicking
 
Signal words: 'at the moment', 'now', 'today', 'this week', 'this month', 'tomorrow', 'next week' (for future arrangements ), 'currently'.