更多"Life on land probably began about 4"的相关试题:
[单项选择]Life on land probably began about 430 million years ago, though it has existed in the water for perhaps as long as 3, 000 mil lion years. When we think of the first life on land, we probably think of strange animals coming out of the oceans, but, in fact, no animals could have been living if plants had not been on land first. Plants had to be on land before animals arrived. They supplied the first land animals with food necessary to live, since they are the only form of life that is able to get and store energy.
The first plants to exist out of the water were probably certain kinds of algae(海藻) which were followed by other plants that grew close to the ground near water and needed water in which to repro duce. Once the move to land had been made, however, evolution (进化) took place quickly. By the end of 100 million years, plants had developed their roots, and some developed tall tree like forms, since height was very important in competing for sunlight. About 300 million ye
A. Algae have existed for more than 430 million years.
B. It is impossible that algae might be the earliest plant on land.
C. Plants get food from animals in the oceans.
D. Evolution began after animals appeared on land.
[填空题]Life on land probably (11) about 430 million years ago，though it has existed in the water for perhaps (12) 3,000 million years．When we think of the first life on land，we probably think of some (13) animals coming out of the oceans，but (14) ，no animals could have been living if plants had not been on land first．Plants had to be on land before animals arrived．They (15) the first land animals with food necessary to live．since they the plants are the only form of life that is able to get and store energy．
[单项选择]Mart’s story in China began many thousands of years ago. Remains of an early form of man discovered in China, known as Peking Man, indicate that Stone Age men lived in the area as long as 500,000 years ago. During the centuries that followed, their
descendants laid the foundations of civilization in Chin
- a.
Throughout its history, China has been a rich source of inventions. Silk, the compass, tea and porcelain originated there. In addition, they are responsible for the invention of paper and printing. The Chinese had used ink as early as 1 200B.C. , an excellent type which they made from lampblack and which is known in English as India ink or China ink. By the end of the first centuryA.D. , the Chinese had invented paper.
The Chinese also invented printing. Early Chinese printing is called block printing. The printer carved raised characters on a block of wood, wet the surface of the characters with ink, and pressed sheets of paper against them. Printers in the
A. Movable type.
B. Baked clay.
C. Block printing.
D. Wet ink.
[填空题]Ethiopia and Egypt now talk about water every year to seek
