The United States Food and Drug Administration has shown itself to be particularly wary with regard to alleged "miracle" drugs in recent times.

General acceptance of 3-D films may prove hard to come ...

单项选择题General acceptance of 3-D films may prove hard to come by as the experience of three decades ago indicated.

Differences in positions adopted by oxygen and hydrogen...

单项选择题Differences in positions adopted by oxygen and hydrogen atoms account for variations in the crystalline structure of different forms of ice.

Many politicians find that they can no longer afford th...

单项选择题Many politicians find that they can no longer afford the luxury of a personal chauffeur.