10 Sulphur has occasionally been found in the earth in an almost pure state.
A regularly
B accidentally
C sometimes
D successfully
11 Do you need anybody to assist you in your work?
A inform
B aid
C direct
D instruct
12 If you have any complaint please see the manager.
A protest
B criticism
C suggestion
D fault
13 Extremely refined behavior， however， cultivated as an art of gracious living， has been characteristic only of societies with wealth and leisure， which admitted women as the social equals of man.
A possible
B typical
C interesting
D morally good
14 Below 600 feet ocean waters range from dimly lit to completely dark.
A inadequately
B hardly
C faintly
D sufficiently
15 Thus our conviction is reinforced that only social revolution can really solve the problems of the people.
A argument
B belief
C proposal
D theory