[填空题]These studies give ______ (leading) results because they haven’t looked at enough cases.

[填空题]Why did he give up his job in the factory Because he had __________.

[单项选择]A. The results of the studies were convincing.
B. The ways the studies were done were strange.
C. The subjects of the studies were not reliable.
D. The researchers of the studies were not objective enough.

[单项选择]Some interviewees lose their chances simply because they fail to display self-confidence.
A. 一些面试者失去了机会，简单地说是因为他们显得没有自信。
B. 一些面试者因为不相信自身的能力而轻易地放弃了这次机会。
C. 一些面试者轻易的放弃了机会，因为他们无法保持自信心。
D. 一些面试者只是因为他们未能表现出自信心而失去机会。

[单项选择]The population of America continues to grow because of ______.
A. its growing birth rates
B. the migration of persons from other countries
C. its good health condition
D. its longer life expectancy

[填空题]We have problem with evaluating risk partly because ______.

[填空题]Maglev trains can run extremely fast partly because they are free from friction by floating on ______.

[填空题]The media has often criticized the Internet because it is dangerous.

[填空题]The people of Savannah offered to surrender because they did not want their city to be set on fire.

[填空题]Solar energy is called a renewable resource because on a human time scale it is essentially inexhaustible, it is expected to last at least 6.5 billion years while the sun completes its life cycle. 46) A potentially renewable resource can be renewed fairly rapidly (hours to several decades) through natural processes, examples of which include forest trees, grassland grasses, wild animals, fresh lake and stream water, groundwater, fresh air, and fertile soil. 　　47) One important potentially renewable resource for us and other species is biological diversity or biodiversity, which consists of the life forms that can best survive variety of conditions currently found on Earth. Kinds of biodiversity include (1) genetic diversity( variety in the genetic makeup among individuals within a single species), (2) species diversity (variety among the species or unique forms of life found in different habitats of the planet), and ( 3 ) ecological diversity (variety of forests, deserts, grasslands,