Question

I am sure(double)put the appropriate adverb​

Answer 1

Answer:

Mangoes carate are kept there double

Answer 2

A word or phrase that qualifies an adjective, verb, or other adverb or a word group is called adverb.

Double is itself an adverb. Also, you can write doubly as the adverb form.

Hence, the sentence will be :-

I am double sure. or, I am doubly sure.

»Both are correct