The relationship between man and animals is close but unequal. Although (61) is true that there are a large (62) of cases of men being the victims of animals(of a man eating tiger, for example), (63) man is the master. (64) the beginning of the human race, animals have been hunted for food. (65) the increasing number of vegetarians in the world, (66) of beef, lamb and pork is (67) consumed(耗费) every day. At work and at play we (68) on animals. Motor transport may have (69) the place of the beast of burden (70) the developed world, but in India life for the farmer would be (71) without the (72) of the cow, and (73) a few third world countries depend on the don-key for transport. We (74) pets at home, and we (75) seeing the elephants play football (76) a monkey play the violin at the circus. The blind have guide dogs, the rich have guard (77) , and (78) the
A. yet
B. but
C. even
D. now
Surprisingly, there is a relationship between sea salt and the making of rain drops. Most of the water droplets that make up clouds are formed around small, solid particles. In order to fall as rain, the cloud droplets have to increase in size. Clouds from which rain does not fall have droplets that are fairly uniform in size. Clouds that produce rain have some droplets that are much larger than others.
The production of rain depends on the presence of the large droplets that grow in size by coalescence (a fusing together). There is evidence to support the theory that a particle of sea salt serves as the nucleus (核,核心) or center, around which the larger droplets form. Most of the sea salt probably enters the atmosphere from, bubbles that form on the surface of the sea. When the bubbles break, a tiny, even microscopic, droplet of salt water is cast into the air. Once in the atmosphere, the microscopic piece of salt collects water vapor from the air. The water vapor then co
A. turn to ice crystals
B. collect on solid particles and condense
C. condense on salt particles
D. rise above the lower level of clouds
我来回答: