stative
🇺🇸
/ˈsteɪtɪv/
🇬🇧
/ˈsteɪtɪv/
relating to a state or condition rather than an action
The verb 'to be' is stative, so it's not used in the progressive tense.
'是'这个动词是状态动词,因此它不用于进行时。