question tag
noun [ C ] uk/ˈkwes.tʃən ˌtæɡ/ us/ˈkwes.tʃən ˌtæɡ/
附加疑问成分，反意疑问句
a short phrase such as "isn't it" or "don't you" that is added to the end of a sentence to check information or to ask if someone agrees with you
In the sentence "It's hot, isn't it?", "isn't it" is a question tag. 这句话中，isn't it 是反意疑问句。