I sit on a chair. 

I am sitting on a chair.

I am sitting on the table.

I am building a house.

I am building a skyscraper.

I am building a tree house.

I break the handle.

I break my pencil.

I break a bone.

I'm running home.

I'm running to workout.

I run to school.

I am writing a dictation.

I write homework.

I'm writing an essay.