Here's how it works:
* be + -ing form of the main verb = present progressive
For example:
* I am walking.
* She is eating.
* They are playing.
Note: The form of "be" changes depending on the subject:
* am for "I"
* is for "he," "she," "it," and singular nouns
* are for "we," "you," and "they," and plural nouns