In bas-relief sculpture, a design projects very slightly from its background, ............ some coins.

Not until Kentucky's Mammoth Cave had been completely explored in 1972 .................................

The Chisos Mountains in Big Bend National park in Texas were created by volcanic eruptions that occurred .........................

.................... the Canadian composer Barbara Pentland wrote four symphonies, three concertos, and an opera, among other works.

........ initial recognition while still quite young.

the sapphire's transparency to ultraviolet and infrared radiation makes ...... in optical instruments.

Mango trees, ...................; densely covered with glossy leaves and bear small fragrant flowers, grow rapidly and can attain heights of up to 90 feet.

According to some indicators, the goal of teaching is to help students learn what ............. to know to live a well-adjusted and successful life.

Computers that once took up entire rooms are now .............. to put on desktops and into wristwatches.

The ponderosa pine is ...... of the most of the timber used by forest-product firms in the Black Hills of South Dakota.