Passage One The Roman language served as the first model for answering the question. Even to someone with no knowledge of Latin, the similarities among Roman languages would have made it natural to suggest that they were derived from a common ancestor. On the assumption that the shared characteristic of these languages came from the common ancestor, it would have been possible to reconstruct many of the characteristics of the original common language. In much the same way it became clear that the branches of the Indo-European family could be studied and a hypothetical family tree constructed, reading back to a common ancestor. This is the tree approach. The basic process represented by the tree model is one of divergence: when languages become isolated from one another, they differ increasingly, and dialects gradually become different until they become separate languages. Divergence is by no means the only possible tendency in language evolution. Johannes Schmidt introduced a 'wave' model, in which linguistic changes were like waves, eventually leading to convergence; that is, growing similarity among languages that were initially quite different. Today, however, most linguists think primarily in terms of familytrees. It is necessary to construct some models of how language change might occur according to a process-based view. There are four main classes of models. The first is the process of initial colonization, by which an uninhabited territory becomes populated; its language naturally becomes that of the colonizers. Second are processes of divergence, such as the linguistic divergence arising from separation or isolation mentioned above in relation to early models of the Indo-European languages. The third group of models is based on processes of linguistic convergence. The wave model, formulated by Schmidt in the 1870's, is an example, but convergence methods have not generally found favor among linguists. Now, the slow and rather static operation of these processes is complicated by another factor: linguistic replacement. That factor provides the basis for a fourth class of models, in many areas of the world the languages initially spoken by the indigenous people have come to be replaced, fully or partially, by languages spoken by people coming from outside. Were it not for this large complicating factor, the world's linguistic history could be faithfully described by the initial distribution of Homo Sapiens, followed by the gradual workings of divergence and convergence. So linguistic replacement also has a key role to play in explaining the origins of the Indo-European languages.

The earth is divided into three main layers—a hard outer crust, a soft middle layer and a center core. The outer crust is broken into massive, irregular pieces called 'plates.' These plates move very slowly, driven by energy forces deep within the earth. Earthquakes occur when these moving plates grind and scrape against each other. In California, the Pacific Plate and the North American Plate meet. The Pacific Plate covers most of the Pacific Ocean floor and the California coastline. The North American Plate stretches across the North American continent and parts of the Atlantic Ocean. The primary boundary between them is the San Andreas Fault. It is more than 650 miles long and extends 10 miles deep. Many smaller faults, such as the Hayward Fault, branch from the San Andreas Fault. The Pacific Plate grinds northwestward past the North American Plate at a rate of about two inches per year. Parts of the San Andreas Fault system adapt to this movement by a constant 'creep' resulting in frequent, moderate, earth tremors. In other areas, movement is not constant and strain can build up for hundreds of years resulting in strong earthquakes when it is released. Unlike other natural disasters, there is no warning for earthquakes. Future earthquakes are a serious threat to Californians, which is why the Fire Department recommends preparing before an earthquake hits.

Biologists have ascertained that specialized cells convert chemical energy into mechanical energy.

Research into the validity of selection methods has consistently shown that the unstructured interview, ______ the interviewer asks any questions he or she likes, is a poor predictor of future job performance.

AI

La Nina phenomenon

推进政务公开

始终把社会效益放在首位

CIA

财政赤字

年终奖

Some historians believe that John Jay could have played ______ in America's history as James Madison.

Can you believe that I won the photo contest with the ______ of the two pictures that was most esthetic, even though I only tried to hang them where there were nails!

People can recognize differences between children and adults. Can you simply say that college students are adults? What events (experiences or ceremonies) make a person an adult? You composition should be no less than 400 words. And please write your composition on the Answer Sheet．

He thumbed through the rose ______ to see if there was anything he fancied for his south-facing wall.

infotainment

As it turned out to be a small house party, we ______ so formally.

残奥会

bill of lading

The majority of nurses are women, but in the higher ranks of the medical profession women are in a ______.