My ................ impression of him is that he is very intelligent and that his poor behaviour is because of boredom.

The government is having difficulties getting people to change their ................ toward use of public transportation.

The governor's efforts to reduce unemployment are failing. She needs a new ........

The union leaders promised to ................ for a longer lunch break for the employees.

He did not ................ to develop a particularly good balance in his own life until he was able to stop worrying about what others thought of him.

Parents often ................ their children's choice of clothes or music.

He ................ failed to mention the unfortunate fact that he had dropped out of college.

The university follows a ................ policy of expelling any student caught plagiarizing.

The most important ................ of the new design is that it consumes less power.

Listening to people is an ................ aspect of good government.

Bats are able to maneuver in the dark even if they are blindfolded, but if their ears are taped shut they cannot find their way. Bats emit very high pitched sound waves through their nostrils. The reflection of these sound waves reaching their sensitive ........... enables bats to avoid obstacles and capture even very tiny insects.

For many years, all ........... were written by hand. Because it took so long to write one book, there were only a few of them. Most people could never own a book. Then sometime between 1450 and 1460, Johannes Gutenberg got the idea of carving separate letters and moving them to make new words. This was the invention of moveable type. From then on, the numbers of books printed grew quickly.

The largest organ in the human body is the skin. One of its functions is to help regulate the amount of body heat that flows in and out of the body. When it is cold, we cover the skin with extra layers of clothing to slow down the outward flow of heat. When it is ........... , evaporation of sweat cools us down.

The solar system is believed to have formed, perhaps 5 billion years ........... , from a spinning cloud of gas called a nebula. As this nebula contracted it began to spin faster and faster and probably, as it became more disk-like, spun off rings of planetary matter. These rings later contracted

In the colder regions of the world, the feathers of birds help retain their body warmth. On the other ........... , the feathers of birds that live in the desert often serve to keep the external heat out. Because of this insulation, there are many kinds of birds that can sit in the desert heat all day and not be harmed by it.