SIMPLE PRESENT AND PRESENT PROGRESSIVE

THE SIMPLE PRESENT
(a) Ann takes a shower every day.
(b) I usually eat lunch at the cafetaria.
(c) Babies cry.
(d) The earth revolves around the sun.
(d) A square has four equal side.
(f) The sky is blue

The simple present expresses daily habits or usual activities, as in (a) and (b).
The simple present expresses general statements of fact, as in (c) and (d).In sum, the simple present is used for events or situation that exist always, usually, or habitually in the past, present, and future.

THE PRESENT PROGRESSIVE
(g) Ann can't come to phone right now because she is taking a shower.
(h) It's noon. I am eating lunch at the cafeteria right now.
(i) Jimmy and Susie are babies. They are crying. I can hear them right now. Maybe they are hungry.

The present progressive expresses an activity that is in progress (is occurring, is happening) right now. The event is in progress at the time the speaker is saying the sentence. The event began in the past, is in progress now, and will probably continue into the future.
FORM : am, is, are + -ing


FREQUENCY ADVERB: ( From 100% of the time to 0% of the time)

100% ----------------------------------------------------------0%
always, usually, often, sometimes, seldom, rarely, never