另外，写摘要时应该使用简单的衔接词，如but，then，thus，yet，for等等，而不能使用at the same time，on the other hand 等。
This paper mainly deals with……
This article focuses on the topics of （that，having，etc）……
This essay presents knowledge that……
This thesis discusses/analyzes……
This paper provides an overview of……
This article compares……and summarizes key findings.
This paper presents up-to-date information on……
This article not only describes……but also suggests……
This paper provides a method of ……
This paper introduces an applicable procedure to analyze……
This paper is devoted to examining the role of……
This paper reflects the state of the art in……
This article reviews the techniques used in……
The writer of this essay tries to explore……
The aim/purpose/objective of this paper is to determine……
How New York Became America's Largest City
In the 18th century New York was smaller than Philadelphia and Boston.Today it is the largest city in America.How can the change in its size and importance be explained？
To answer this question we must consider certain facts about geography，history，and economics.Together these three will explain the huge growth of Americas most famous city.
The map of the Northeast shows that four of the most heavily populated areas in this region are around seaports.At these points materials from across the sea enter the United States，and the product of the land are sent there for export across the sea.
Economists know that places where transportation lines meet are good places for making raw materials into finished goods.That is why seaports often have cities nearby.But cities like New York needed more than their geographical location in order to become great industrial centers.Their development did not happen simply by chance.
About 1815，when many Americans from the east coast had already moved toward the west，trade routes from the ports to the central regions of the country began to be a serious problem. The slow wagons of that time，drawn by horses or oxen，were too expensive for moving heavy freight very far. Americans had long admired Europe's canals.In New York State a canal seemed the best solution to the transportation problem.From the eastern end of Lake Erie all the way across the state to the Hudson River there is a long strip of low land.Here the Erie Canal was constructed. After several years of work it was completed in 1825.
The canal produced an immediate effect.Freight costs were cut to about one-tenth of what had been.New York City，which had been smaller than Philadelphia and Boston，quickly became the leading city of the coast.In the years that followed，transportation routes on the Great Lakes were joined to routes on the Mississippi River.Then New York City became the end point of a great inland shipping system that extended from the Atlantic Ocean far up the western branches of the Mississippi.
The coming of the railroads made canal shipping less important，but it tied New York even more closely to the central regions of the country.It was easier for people in the central states to ship their goods to New York for export overseas.
Exports from New York were greater than imports.Consequently，shipping companies were eager to fill their ships with passengers on the return trip from Europe.Passengers could come from Europe very cheaply as a result.
Thus New York became the greatest port for receiving people from European countries. Many of these people remained in the city.Others stayed in New York for a few weeks，months，or years，and then moved to other parts of the United States.For these great number of new Americans New York had to provide homes，goods，and services.Their labor helped the city be come great.
How New York Became America's Largest City
New York was once smaller than Philadelphia and Boston，but now it is America's largest city because of geography，history and economics.
New York was located at the seaport where materials were imported to the US and the products of the US were sent abroad across the sea.The city was further developed when the Erie Canal was completed in 1825.This linked Lake Erie to New York via the Hudson River and the cost of transporting goods to those who had settled inland was cut down.In addition，the Great Lakes were soon linked to the Mississippi.Later，railroads tied New York closer to the central states，whose goods were exported via New York.Fewer goods were imported，so cheap passages were available from Europe.New York became the main port for receiving Europeans，many of whom stayed in the city and helped it become great.
The report is hereby made to ask for the approval of the board for the solution of the problem.
This report will summarize……
The report provides an introduction to……
The operation on…… is under smooth way.
This report only provides guidelines they can use to assess their own needs.
May I have your approval of……by the end of this month？
We will fulfill the task ahead of time.
Upon the request of the committee，we have conducted the report.
Subject：Ship Accident off West Coast of The Yangtze River，No Casualties.
Yesterday evening two boats collided in thick fog in The Yangtze River not far from Wu Han. One was a cargo ship carrying lumber，apparently on its way to The Yangtze River. The other was a National ferry on its regular run from Jiu Jiang to Wu Han.
However，because of the weather conditions，the captains did not realize the danger until a few seconds before the collision took place. Consequently，there was no time for them to prevent the accident.
Fortunately，there were no casualties among the crews or passengers，but both ships suffered badly damages.
A spokesman for the port authorities said that a committee would be set up to determine the cause of the collision.