1. I usually take the stairs instead of taking the elevator.
2. I usually use the stairs instead of using the elevator.
(Are borth grammatical? Do we have to use only 'take'? )
Both are correct and commonly used.
Both are correct.
Both sentences are grammatically correct, and you can use either "take" or "use" in this context.
The verb "take" is commonly used to refer to using stairs because it indicates physically moving one's body upwards by stepping on each step. So, saying "take the stairs" implies using the stairs as a means of transportation.
On the other hand, the verb "use" is more general and can be used for any kind of tool or facility, including elevators. So, saying "use the stairs" is also correct because it indicates utilizing the stairs as a method of getting to a higher floor.
Ultimately, whether you choose to use "take" or "use" depends on your personal preference and the context in which you are speaking. Both options convey the same meaning.