1 . (2018·全国Ⅱ)Corn production has jumped nearly 125 percent over __________ past 25 years, while rice has increased only 7 percent.

2 . Of ________ nineteen recognized polar bear subpopulations，three are declining，six are stable，one is increasing，and nine lack enough data. (用适当的词填空)

3 . She told me she had searched the room for the amber _______ day before but without success. （用适当的词填空）

4 . In ________ 1600’s, Shakespeare made use of ________ wider vocabulary than ever before.

A．the; /

B．/ ;/

C．the; a

D．/; a

5 . —Did you enjoy yourself yesterday?
—Yes. As you know, ________ party went on in ________ most pleasant atmosphere.

A．the…a

B．the…the

C．a…the

D．a…a

6 . Five years ago her brother was ______ university student of______ physics．

A．an; the	B．a; 不填
C．an; 不填	D．a; the

7 . American films always have ______ edge on foreign films at ______ Oscars, regardless of how popular a foreign film might be.

A．an; the

B．the; the

C．an; /

D．the; /

8 . When he discovered that it was all ______ joke, he laughed so hard that he nearly fell to _____ ground.

A．a; 不填	B．the; 不填
C．a; the	D．the; a

9 . ______ strong and powerful China will certainly benefit ______ whole world.

A．A; a	B．The; a
C．The; the	D．A; the

10 . Some experts say ____ birthrate of China, after the one-child policy is relaxed, can see ___ modest increase in future.

A．the, a

B．a, a

C．a, /

D．the, /