Simple present

Present simple 

Positives, Negatives and question

For the plural use: Does in negativa and question. (we,they and you) 

Example: 

They do not run every morning.  -

Do they run evey morning?

They run every morning. + 

For the singular use: Does for the negative and questions. (she, he or it) 

Example: 

Does she eat every nigth? 

She does't eat every nigth. - 

She eat  every nigt. + 

When they are in singular the verb is added "s" Example: Works