Use 'do not' before a verb to make a negative sentence in Simple Present. The contracted form is 'don't':
- I do not (don't) eat meat.
- You do not (don't) exercise often.
- We do not (don't) speak Italian.
- They do not (don't) work.
For the third person singular (he, she, it) use 'does not' (contracted form 'doesn't') before the verb, and don't add the 's' to the verb:
- He does not (doesn't) teach Italian.
- She does not (doesn't) like dogs.
- It does not (doesn't) rain here often.
Note that to form a negative sentence, we do not make the verb negative. "I eat not meat" is wrong. We add a helping verb 'do' and make 'do' negative: "I do not eat meat."
Remember that the verb 'be' does not need a helping verb. We can make it negative:
- I am not Russian.
- You are not Russian.
- He/she/it is not Russian.
- We are not Russian.
- They are not Russian.