问题补充:
Doctors believe that only a small number of people of this kind of disease.
A. is in danger
B. is in a danger
C. are in danger
D. are in the danger
答案:
A. is in danger
B. is in a danger
(答案→)C. are in danger
D. are in the danger
解析:考查主谓一致。A number of +复数名词作主语谓语用复数形式。处于危险中be in danger of注意danger 前不用任何冠词。医生认为只有一小部分人有危险得这种病。