about a tense

[ivygreen]

Could you tell me why "being" is needed in this sentence below.
"I can't understand why you (are being) so mean. You are always very kind to me."

In this case, I chose "(are)" .

[bianca]

Usually, you are not mean, but now, at this very moment, you are being mean. This is not like you.

[Dr. Jamshid Ibrahim]

Could you tell me why "being" is needed in this sentence below.
"I can't understand why you (are being) so mean. You are always very kind to me."

In this case, I chose "(are)" .

Verb to be is usually a stative verb (used in the simple tense) not really used in a dynamic sense (continuous tense) but it can be used dynamically when it it refers to a momentary/temporary situation (often in a negative way) as Bianca said you are not mean "as a rule":
You are being nasty to me (these days, at the moment..)

[albertino]

Verb to be is usually a stative verb (used in the simple tense) not really used in a dynamic sense (continuous tense) but it can be used dynamically when it it refers to a momentary/temporary situation (often in a negative way) as Bianca said you are not mean "as a rule":
You are being nasty to me (these days, at the moment..)

Out of character temporarily. I do so, sometimes.

[Dr. Jamshid Ibrahim]

Out of character temporarily. I do so, sometimes.

No wonder why to be (as a link verb) takes the adjective and not the adverb.

[ivygreen]

Thank you very much for all of you.
I understand well about this question.