Does the thin mountain air agree ___ you?
A.to
B.with
C.on
D.for
Ultrasonic sounds produce pulsed signals ___ various defects in metal can be detected.
A.for which
B.of which
C.as a result of which
D.by means of which
___, it is quite easy to drill a hole in it with laser.
A.Hard although a diamond is
B.As a diamond is hard
C.Hard as a diamond is
D.How hard is a diamond
In the lecture ___ he will tell us somethingabout modern English usage.
A.following
B.followed
C.to follow
D.being followed
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