Each week , we explore words and expressions in American English . Today's expression comes from the world of animals ! The expression is “eager beaver .” By definition , an eager beaver is a person who seems full of energy and a good attitude . These people are willing to do what others expect and often do things as quickly as they can . And they are enthusiastic ! A great word that means the same thing (a synonym ) is go-getter . A person who is a real go-getter gets the job done ! For an example of how to use the term eager beaver , try to imagine a mathematics class . The teacher tells students that they must solve 100 math problems before coming to school the next day . Most of the students are unhappy about having so much homework ! But not all . A few students do not mind the work at all . They are eager beavers . They love to do math problems and cannot wait to get started . In fact , they do more than 100 math problems ! Eager beavers often go above and beyond . Eager beavers can work in any industry . From law to I.T . from medicine to fashion – these people arrive before anyone else , and are usually the last ones to leave . These men and women work hard because they enjoy their jobs . Speaking of the word “industry ,” makes me think of another synonym : industrious . Eager beavers are nothing if not industrious . This expression , of course , comes from the name of the hardworking animal the beaver ! They are rodents , like mice and rats . But beavers are much larger . Beavers have a large flat tail to help them swim . They also have thick brown fur , or hair , to keep them warm in cold water . And they have front teeth sharp enough to cut down large trees . Beavers spend a lot of time in the water , building dams to create small lakes or ponds . They work hard to cut down trees , remove branches , and put them together with mud to make dams . That is why we call the beaver nature's architect . Few other animals work so hard . Historians say the beaver had an important part to play in the European settlement of North America . There were many millions of beavers when European settlers first arrived . The settlers put great value on the fur of the beaver . In fact , beaver was the most valuable fur in North America . Beaver skins often were used as money . People looking for adventure traveled west across the country to search for beaver . In their search , they explored much of the western territories . Trading posts are the places where trappers exchanged beaver skins for the goods they needed . Some trading posts became villages and later towns and cities . Many of the beaver trappers became guides in these territories as more people moved into them . They led groups of settlers to new homes in the West . But laws were passed to protect the beaver . And , like the animal , the expression “eager beaver ” is alive and well in the United States !