Time frame shifts.

Simple tenses include the simple present, simple past and simple future. They have the following uses:

Time Frame	Examples	Use
Present Past future	(a) Our in –groups help to define or values. (b) Immigrants to America in the mid nineteenth century included large numbers of Chinese. © Families will always be important to most of us.	To express general ideas, relationships and truths.
Present. Past Future	(d) Our family visits my grandparents after church every Sunday. (e) Almost every year we celebrated my great aunt’s birthday with a family picnic. (f) The club will collect clues once a month.	To describe habitual actions.
Present Past Future	(g) Kay thinks she has chosen the right profession. (h) People once believed that earth was flat. (i) You will love our new puppy.	To describe mental perceptions or emotions.
Present Past Future	(j) Mark has three brothers (k) We owned a SUV, but we traded it in for a hybrid car. (l) By next month, Hannah will have a new computer.	To express possessions or personal relationships.
Present Past Future	(m) The environmental agency reports that the new evidence has been gathered about global warming. (n) When the United States passed the Chinese Exclusion Act in 1881, 100,000 Chinese were living in the United States. (o) Mario will call you Thursday morning; I hope you will not have left for Omaha by then.	To establish the time frame and the moment of focus.