Answer:
frightened / quickly / terrifying
Step-by-step explanation:
The first blank must be filled in with a word that has "ed" in the end, this is because that the feeling is in past tense. The word "looked" indicates this. Cross out the answers that do not have frightened for the first answer.
Now the second blank describes an action, meaning that it must end the letters "ly" in the end, cross out the answer without "ly" for the ending. This leaves us with the only non-crossed out answer [frightened / quickly / terrifying]