单项选择

• 1、

  The study also notes a steady decline in the numbe

• 2、

  Enamel,the hardest substance in a human being's bo

• 3、

  Many economists have given in to the fatal lure of

• 4、

  Our statistics show that we consume all that we ar

• 5、

  He impressed all his colleagues as a vigorous man

• 6、

  Unable to control himself, he tore the phone from

• 7、

  People who do not sleep enough tend to become irri

• 8、

  Michael is now merely a good friend.（　）

• 9、

  He is said to be suffering from terminal cancer an

• 10、

  Mr. Henley has accelerated his sale of shares over

• 11、

  It is useless to argue with him once he has made u

• 12、

  The little boy can't discriminate the right thing

• 13、

  Mary is looking for the book she lost yesterday（　）

• 14、

  The dentist has decided to extract her bad tooth.（

• 15、

  Thousands of people perished in the storm.