In 1861 it seemed inevitable that the Southern states would break away from the Union.

Some sea urchins海胆 have venomous (toxin) spines

The company issues an annual report every March.

Bats fly, rather than glide, and thus are the only mammals capable of true flight.

In 1974 Henry Aaron broke Babe Ruth's monumental lifetime record of 714 home runs.

Mary McCarthy s satires 讽刺文学 are couched in a prose style that has a classic precision.

The future survival of the bald eagle is still an important American ecological concern.

Formerly , in the United States, many nurses worked as private duty nurses rather than in hospitals.

A mythical(imaginary) creature, the dragon was believed to have lion's claws, scaly skin, and fiery breath.

Formulated in 1823, the Monroe Doctrine asserted that the Americas were no longer open to European colonization.