Теорія:

Present simple
 
Use:
  
Something that is true in the present:I’m a student.
Something that happens again and again in the present:I play football every weekend.
Something that is always true:The adult human body contains 206 bones.
Something that is fixed in the future:The school term starts next week.
For habits:She only eats fish.
For instructions or directions:Open the packet and pour the contents into hot water.
We use words like 'sometimes', 'often', 'always', and 'never' (adverbs of frequency) with the present tense:I sometimes go to the cinema.
 
Sentences:
  
Affirmative
I, you, we, they – use the base form of a verb
He, she, it – add 's' to the verb
I eat lunch at noon.
She eats lunch at noon.
Negative
I, you, we, they – do not (don't)
He, she, it – does not (doesn't)
We don't eat lunch at noon.
He doesn't eat lunch at noon.
Questions
I, you, we, they – do
He, she, it – does
Do you eat lunch at noon?
Does she eat lunch at noon?
 
Verb 'to be'
  
I
am
I am thirsty.
I am not thirsty. (I'm not thirsty)
Am I thirsty?
He, she, itis
She is thirsty.
He is not (isn't) thirsty.
Is it thirsty?
You, we, theyare            
They are thirsty.
We are not (aren't) thirsty.
Are you thirsty?
 
Verb 'to have'
 
Ihave
I have a dog.
I don't have a dog. / I haven't got a dog.*
Do I have a dog? / Have I got a dog?
He, she, ithas
He has a dog.
She doesn't have a dog. / She hasn't got a dog.*
Does he have a dog? / Has she got a dog?
You, we, theyhave
You have a dog.
We don't have a dog. / We haven't got a dog.*
Do they have a dog? / Have they got a dog?
 
*'Have got' is mainly used in British English. You can also use 'have' on its own (especially in American English). In this case, however, you must form negative sentences and questions with the auxiliary verb 'do'.
  
As you can see, we usually just add the ending -s (play – plays) to the verbs in third person singular (he, she, it) but there are some exceptions:
 
The verbs 'can', 'may', 'might', 'must' remain the same in all forms. So don't add -s.he can, she may, it must
Verbs ending in -o, -a, -ch, -sh, -s, -x, add -es instead of -s.
do – he does,
wash – she washes
Final -y after a consonant becomes -ie before -s.worry – he worries
Final -y after a vowel a, e, i, o, u is not modified.play – he plays
  
Signal words: 'every day', 'often', 'always', 'sometimes', 'never', etc.