Verb types and the "present tense"

The present tense in Japanese is used to describe one of two things:  1) an activity a person habitually or regularly engages in, or 2) an activity that a person is planning on performing or doing in the future.

Habitual actions:

わたしはよくテレビをみます。                I often watch TV.

メアリーさんはときどきあさごはんをたべません。Mary sometimes doesn't eat breakfast.
                                          

Future actions:

わたしはあしたきょうとにいきます。                      I will go to Kyoto tomorrow.

スーさんはきょううちにかえりません。                   Sue will not return today.