Crossword puzzle clue "surely can't be serious"

to breathe convulsively

(South African) is it? an expression used in response to a statement, sometimes to seek confirmation but often merely to show that one is listening

a word used to modify the meaning of a verb, adjective, or other adverb

ADVERB, a word used to modify the meaning of a verb, adjective, or other adverb

to declare positively

to wager