Question

add a question tag to sentence - its very hot today

Answer 1

isn't it a very hot day ?

Answer 2

Answer: It’s very hot today, isn’t it?

Explanation:

The question tag is used to easily create an interrogative sentence.  

In this, the statement will be kept intact but at the end interrogative clause will be added. The interrogative clause will be made by writing the negative form of “be” verb or “do” verb in the statement with the corresponding pronoun.

In the present case, the “be” verb is “is” so the negative of it will be “isn’t”.