Đề thi thử THPT Quốc gia môn Tiếng Anh trường THPT Chu Văn An – Hà Nội năm 2015

Because hunter-gathers have fared poorly in comparison with their agricultural cousins, their numbers have dwindled, and they have been forced to live in the marginal wastelands. In higher latitudes, the shorter growing season has restricted the availability of plant life. Such conditions have caused a greater dependence on hunting and, along the coasts and waterways, of fishing. The abundance of vegetation in the lower latitudes of the tropics, on the other hand, has provided a greater opportunity for gathering a variety of plants. In short the environment differences have restricted the diet and have limited possibilities for the development of subsistence societies.

Contemporary hunter-gatherers may help us understand our prehistoric ancestors. We know from observation of modern hunter-gatherers in both Africa and Alaska that a society based on hunting and gathering must be very mobile. Following the food supply can be a way of life. If a particular kind of wild herding animal is the basis of the food for a group of people, those people must move to stay within reach of those animals. For many of the native people of the great central plains of North America, following the buffalo, who were in turn following the growth of grazing foods, determining their way of life.

Đáp án : Hunting and gathering

Đáp án : Studying them gives us insights into the lifestyle of prehistoric people.( Nghiên cứu về chúng đem lại cho chúng ta cái nhìn sâu về lối sống của người tiền sử.)

Although only a small percentage of the electromagnetic radiation that is emitted by the Sun is ultraviolet (UV) radiation, the amount that is emitted would be enough to cause severe damage to most forms of life on Earth were it all to reach the surface of the Earth. Fortunately, all of the Sun’s ultraviolet radiation does not reach the Earth because of a layer of oxygen, called the ozone layer, encircling the Earth in the stratosphere at an altitude of about 15 miles above the Earth. The ozone layer absorbs much of the Sun’s ultraviolet radiation and prevents it from reaching the Earth.Ozone is a form of oxygen in which each molecule consists of three atoms (O3) instead of the two atoms (O2) usually found in an oxygen molecule. Ozone forms in the stratosphere in a process that is initiated by ultraviolet radiation from the Sun. UV radiation from the Sun splits oxygen molecules with two atoms into free oxygen atoms, and each of these unattached oxygen atoms then joins up with an oxygen molecule to form ozone. UV radiation is also capable of splitting up ozone molecules; thus, ozone is constantly forming, splitting and reforming in the stratosphere. When UV radiation is absorbed during the process of ozone formation and reformation, it is unable to reach Earth and cause damage there.

Recently, however, the ozone layer over parts of the Earth has been diminishing. Chief among the culprits in the case of the disappearing ozone, those that are really responsible, are the chloroflurocarbons (CFCs). CFCs meander up from the Earth into the stratosphere, where they break down and release chlorine. The released chlorine reacts with ozone in the stratosphere to form chlorine monoxide (CIO) and oxygen (O2). The chlorine then becomes free to go through the cycle over and over again. One chlorine atom can, in fact, destroy hundreds of thousands of ozone molecules in this repetition cycle, and the effects of this destructive process are now becoming evident.

The link between mustard, a type of sauce, and Norwich (3) _______ back to the nineteenth century. Jeremiah Colman began to make mustard in 1814 in a nearby village. The yellow fields, full of mustard flowers whose seeds were required for Colman’s factory, soon changed the appearance of the local (4) _______. The company (5) _______ rapidly and in 1854 it moved to a suburb on the outskirts of Norwich. By this time, Colman’s mustard was famous in many countries. The company is still in (6) _______ and many people continue to enjoy eating mustard with meat, cheese and other food.