Formation: The Present Indefinite is the first form of the verb the infinitive without the particle to

The Present Indefinite tense
Formation: The Present Indefinite is the first form of the verb (the infinitive without the particle to) for all persons singular and plural except the third person singular where the suffix -s (-es) is added to the stem of the verb.
The negative and interrogative forms are formed by means of the auxiliary verb to do in the Present Indefinite (do / does).
Note: The contracted negative forms are don't and doesn't.
Use:

1. 
   The Present Indefinite denotes a customary repeated action in the present.
   

I usually get to my office by underground.

Note: The Present Indefinite is often accompanied by the adverbs often, seldom, sometimes, always, usually. They are placed before the notional verb but after the verb to be.
Julia is often late for her work. = Julia often comes late to her work.

2.The Present Indefinite is used to denote a future action in adverbial clauses of time and condition, because no future tenses can be used in these types of subordinate clauses.

Let him call me back as soon as he comes home.
I'll do this work if you pay me one thousand dollars.

2.The Present Indefinite can be used to denote a future action which will take place in the near future and regarded as fixed.

Manchester United plays with Liverpool on Sunday.

3.The Present Indefinite is used to denote an action in progress going on at the present moment for verbs that are not used in continuous tenses.

I see a boat with a man in it.

4.The Present Indefinite is used to characterize a person or an object.

Nick never comes at the last moment.

5.The Present Indefinite is used in sentences of the type:

Why don't you speak to the general manager?

6.The Present Indefinite is used in theatrical remarks.

The student goes to the teacher's table.

7.The Present Indefinite is used to denote universal truths.

Two multiplied by two equals four.