单项选择题 Obsessed with their research on superconductive material, they were oblivious ofthe goings-on around them.

单项选择题 Recurrent showers were forecast for the day.

单项选择题 A careful screeningof the disease will lessen the patients" anxiety.

单项选择题 Those infected with the virus of hepatitis B enjoy equal rights underthe provisions of the law.

单项选择题 It is suggested by the authors of the paper that their subjects are more proneto get heart disease than other groups.