Page 15 16 usage note

1. Page 15
16. Usage Note: Present Progressive with Be

2. We sometimes use the progressive form of the verb
be + an adjective to show that a state is temporary
or changing.
Action Meaning Non-Action Meaning
You are being silly. (=You are acting
in a silly manner right now.)
You are silly. (= In general, you are a
silly person.)
Why is he being so rude? (= His
rudeness is temporary. He’s not
usually rude.
Why is he so rude? (= In general, he is
a rude person.)