Use it to talk about things that are happening right now! Think of it as progress in the present: working, shopping, talking, studying.
The Present Progressive is equivalent to the ing ending in English. It's easy to learn. There is no irregular verb in the present progressive in Portuguese. Furthermore, the conjugations are the same for all the different persons of speech: eu, você, ele, a gente, nós, vocês, eles.
The verb estar is always right before the verb in the this tense. That's because the grammar is identical to English in that you/he/she/we/they are doing something. The formation is totally consistent and there are no irregulars at all.
|She's arriving||Ela está cheg||ando|
|Who's talking?||Quem está fal||ando?|
|I'm eating.||Eu estou com||endo|
|He's losing.||Ele está perd||endo|
|He's insisting.||Ele está insist||indo|
|She's driving.||Ela está dirig||indo|