Travelling _____ air is faster than travelling _____ sea.
A. on; on
B. by; by
C. in; on
D. by; at
A. on; on
B. by; by
C. in; on
D. by; at
A. for; in
B. so; that
C. in; at
D. for; during
A. in; on
B. at; in
C. at; on
D. by; during
A. on
B. during
C. by
D. for
A. in
B. off
C. over
D. up
A. of
B. off
C. between
D. with
A. by
B. among
C. towards
D. during
A. in
B. about
C. over
D. around
A. in
B. on
C. to
D. by
A. for
B. by
C. to
D. with