The first plant-like organisms probably_____ in the sea, perhaps three billion years ago.

In male pattern baldness, ______ strongly influences the degree of hair loss.

In Watch the Skies, Curtis Peebles ______ attempt to explain America’s belief in flying saucers

The irregular coastline of ______ a succession of bays and inlets, with the hook of the Cape Cod peninsula in the southeast.

I forgot my coat______ I got very cold.

______ arrived at the library, he started to work immediately.

A spacecraft is freed from friction ________launched into space.

_____with their surroundings, or they hide in crevices for protection.

_____a ball-and-socket joint, the elbow is a simple hinge joint.