Form and rules
How it works
Use the present simple for routines, repeated actions and facts: I work on Mondays.
Use the present continuous for actions happening now or around now: I am working at home today.
State verbs such as know, like, need and understand are normally not used in the continuous.
Time expressions help: usually and every day often signal simple; now and this week often signal continuous.
Use do/does for present-simple questions, but am/is/are for present-continuous questions.