The use of the chemical may present a certain hazard to the laboratory workers.()

单项选择题Do you believe these two intimate friends used to be enemies()

A. bearable
B. internal
C. close
D. believable

单项选择题He has trouble understanding that other people judge him by his social skills and conduct().

A.style
B.behavior
C.mode
D.attitude

单项选择题It seems that only Mary is eligible for the job.()

A. prepared
B. trained
C. qualified
D. guided

单项选择题A great deal has been done to remedy the situation().

A. maintain
B. improve
C. assess
D. protect

单项选择题At 90, many individuals still remain healthy and energetic.()

A. intelligent
B. rough
C. robust
D. revivable