If you want to have strong bones you should eat food ______ .

填空题Fruits, such as watermelon, red grapefruit, and guava, are now exciting the interest of researchers because ______ .

填空题A study shows that men who eat tomato products twice a week could probably avoid developing prostate cancer by one third in comparison with those ______ .

填空题Investigators don’t ______ how many phytochemicals exist and how they work.

填空题Researchers say that supplements can completely take the place of real food in the near future.

填空题It is proved that the uncontrolled activity of free radicals caused many cancers.