2019-05-24 15:13 供稿单位: 未知 责编:青岛朗阁 浏览次
摘要： 正在进行雅思备考的小伙伴，你们想知道2019年5月23日雅思考试的考试内容吗?今天为了帮助大家更好的备战雅思，青岛朗阁雅思阅读名师 曲志国老师就为大家带来2019年5月23日雅思阅读考试真题回顾。
Reading Passage 1 Title: 核磁共振理论 Question types: 标题配
文章内容回顾 主要讲述了核磁共振这种物理现象。 相关英文原文阅读 Nuclear magnetic resonance (NMR) is a physical phenomenon based upon the quantum mechanical magnetic properties of an atom's nucleus. NMR also commonly refers to a family of scientific methods that exploit nuclear magnetic resonance to study molecules.
All nuclei that contain odd numbers of protons or neutrons have an intrinsic magnetic moment and angular momentum. The most commonly measured nuclei are hydrogen-1 (the most receptive isotope at natural abundance) and carbon-13, although nuclei from isotopes of many other elements (e.g. 15N, 14N 19F, 31P, 17O, 29Si, 10B, 11B, 23Na, 35Cl, 195Pt) can also be observed.
NMR resonant frequencies for a particular substance are directly proportional to the strength of the applied magnetic field, in accordance with the equation for the Larmor precession frequency.
NMR studies magnetic nuclei by aligning them with an applied constant magnetic field and perturbing this alignment using an alternating electric field, those fields being orthogonal. The resulting response to the perturbing magnetic field is the phenomenon that is exploited in NMR spectroscopy and magnetic resonance imaging, which use very powerful applied magnetic fields in order to achieve high resolution spectra, details of which are described by the chemical shift and the Zeeman effect.
NMR phenomena are also utilised in low field NMR and earth's field NMR spectrometers, and some kinds of magnetometer.
剑桥雅思推荐原文练习 剑6 Test4 Passage3
Reading Passage 2 Title: 大猩猩文化 Question types: 配对题
文章内容回顾 讲述了大猩猩这一物种的社会结构和文化体系。 题型技巧分析 判断题做题流程：
u NOT GIVEN：题目中有一处或多处信息在原文无法得到证实，其余信息都可在原文得到证实，且证实为与原文表述一致。
u 答案分布规律：若数量大于或等于三，则三种答案均会出现，NOT GIVEN 数量最少，TURE/FALSE数量相当。
题型难度分析 本篇文章有较多配对题，难度适中。 剑桥雅思推荐原文练习 剑6 Test 2 Passage 3
Reading Passage 3 Title: 语言的发展 Question types: 判断题
文章内容回顾 主要讲述了语言的发展历史。 相关英文原文阅读 The emergence of language was a defining moment in the evolution of modern humans. It was an innovation that changed radically the character of human society. Here, we provide an approach to language evolution based on evolutionary game theory. We explore the ways in which protolanguages can evolve in a nonlinguistic society and how specific signals can become associated with specific objects. We assume that early in the evolution of language, errors in signaling and perception would be common. We model the probability of misunderstanding a signal and show that this limits the number of objects that can be described by a protolanguage. This “error limit” is not overcome by employing more sounds but by combining a small set of more easily distinguishable sounds into words. The process of “word formation” enables a language to encode an essentially unlimited number of objects. Next, we analyze how words can be combined into sentences and specify the conditions for the evolution of very simple grammatical rules. We argue that grammar originated as a simplified rule system that evolved by natural selection to reduce mistakes in communication. Our theory provides a systematic approach for thinking about the origin and evolution of human language.
Language remains in the minds of many philosophers, linguists, and biologists a quintessentially human trait (1–3). Attempts to shed light on the evolution of human language have come from many areas including studies of primate social behavior (4–6), the diversity of existing human languages (7, 8), the development of language in children (9–11), and the genetic and anatomical correlates of language competence (12–16), as well as theoretical studies of cultural evolution (17–21) and of learning and lexicon formation (22). Studies of bees, birds, and mammals have shown that complex communication can evolve without the need for a human grammar or for large vocabularies of symbols (23, 24). All human languages are thought to possess the same general structure and permit an almost limitless production of information for communication (25). This limitlessness has been described as “making infinite use of finite means” (45). The lack of obvious formal similarities between human language and animal communication has led some to propose that human language is not a product of evolution but a side-effect of a large and complex brain evolved for nonlinguistic purposes (1, 26). Others suggest that language represents a mix of organic and cultural factors and, as such, can only be understood fully by investigating its cultural history (16, 27). One problem in the study of language evolution has been the tendency to identify contemporary features of human language and suggest scenarios in which these would be selectively advantageous. This approach ignores the fact that if language has evolved, it must have done so from a relatively simple precursor (28, 29). We are therefore required to provide an explanation that proposes an advantage for a very simple language in a population that is prelinguistic (30–32). This work can be seen as part of a recent program to understand language evolution based on mathematical and computational modeling.
题型难度分析 本篇文章总体上难度较大。 题型技巧分析 选择题做题步骤：
剑桥雅思推荐原文练习 剑5 Test 4 Passage2 考试趋势分析和备考指导：