A.unless
B.whether
C.in case
D.only if

A.As long as
B.Whether
C.Unless
D.Even if

A.front
B.above
C.over
D.ahead

A.face
B.deal
C.encounter
D.challenge

A.refusal
B.question
C.challenge
D.obstacle

A.influencing
B.determining
C.controlling
D.pointing

A.able
B.available
C.availability
D.suitable

A.make
B.turn
C.figure
D.look

A.feedback
B.incentive
C.information
D.opinion

A.match
B.fit
C.go
D.agree