For some time the expert __________ people of the health risks caused by passive smoking. He     says he won’t stop until all the smokers around him decide to quit smoking. 
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A
is warned
B
is warning
C
has been warning
D
has been warned
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Mr.Wang ______ two boys to send the sick boy to the nearest hospital.
#104349
A
arranged
B
has arranged
C
had arranged for
D
has arranged for
Many British people have noticed that butterflies _______ from its natural habitats during the past several years.
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A
are disappearing
B
have been disappeared
C
have been disappearing
D
will have disappeared