While other scientists are keeping____eye on changes in the H5N1 bird flu strain, the scientists in England are working on vaccines, in case it becomes highly infectious in ____humans.
#9824
A
a , /
B
an, /
C
the, an
D
an, the
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Four and half hours of discussion took us up to midnight,and Break for cheese,chocolate and tea with sugar.
#8428
A
a;a
B
the; the
C
不填；the
D
a;不填
Because he has been out of _____ work for months, Jack now has to depend on his parents for _____living.
#8880
A
/; a
B
the; a
C
/;/
D
the; /
Every year in China, ______ day is set aside to honor and show respect to ______ elders.
#8556
A
/; the
B
the; the
C
a; /
D
a; the
The Diaoyu Islands, which lie in ____ East China Sea between China and Japan have belonged to China since ____ ancient times．
#8435
A
the; the
B
the;/
C
/; the
D
/ ; /
John Hope Franklin was _______ respected historian and social activist, who wrote about race and _______ struggles of black Americans.
#9911
A
the, a
B
a, the
C
a, /
D
/, the