•Paragraph Unity

–Topic Sentences

•Paragraph Coherence

–Transitional Devices

•Transitional Words and Phrases

•Common Transitional Words and Phrases

–Linking Pronouns

–Repetition of Key Words

•Paragraph Development

–Exemplification

–Narration

–Process

–Description

–Comparison and Contrast

–Analogy

–Cause and Effect

–Classification and Division

–Definition

–Analysis

–Enumeration

•The latest electronic innovation, still under development,is called "adaptive optics."

Adaptive optics is an electronic feedback mechanism capable of correcting for the distorting

effects of the earth's atmosphere and thus allowing much sharper images of astronomical

objects. The earth's atmosphere is constantly shimmering, because of moving pockets of air

and changes in temperature, and such shimmering causes passing light rays to bend one

way then another. In effect, the shifting atmosphere acts as a rapidly changing lens,

smearing out and defocusing images. In adaptive optics, motorized cushions a replaced

behind the telescope's secondary mirror and constantly reshape the mirror's surface to

counteract the defocusing effect of the atmosphere.

The cushions are given instructions by a computer, which analyzes the image of a

"guide star" in the same field of view as whatever the telescope is looking at. With no

atmospheric distortion, the image of a star should be a single point of light. By analyzing

how the actual image of the guide star differs from a point, the computer can infer the

distortion of the atmosphere and tell the cushions how to alter the mirror to bring the guide

star, and all the objects near it, back into sharp focus. Corrections must be made rapidly,

because the atmosphere is rapidly shifting. In practice, the computer will analyze the image

of a guide star and give new instructions to the reshaping cushions every 0.01 to 0.1

seconds.

time in much the same way as the illustrious Briton did more than 300 years ago. Most of

the laws of physics continue to be written in the style of Newton; they are designed to show

how things change from one moment to the next. Each event under study, such as the path

of a ball thrown into the air or the thermodynamics of a melting ice cube, is broken down into

a series of freeze-frames that, run like a movie, show how nature works.

Newton had placed a clock upon the mantel of the universe. This Newtonian timepiece

ticked and ticked, chiming like some cosmic Big Ben, in step with all the celestial inhabitants,

no matter what their speed or position. That meant that a clock situated at the edge of the

universe or zipping about the cosmos at high velocities would register the same passage of

time, identical minutes and identical seconds, as an earthbound clock. More important, the

Newtonian clock was never affected by the events going on around it. Time was aloof and

absolute, alike for all as galaxies collided, solar systems formed, and moons orbited planets.

•Limited investment in the housing sector makes it practically impossible to allocate

sufficient resources for urban dwellers' housing needs. A high rate of urban population

growth has increased the country's needs for housing. A small group of city officials has laid

out a new plan to combat the crisis. A solution to the housing-shortage problem is a vital

policy issue here. The housing problem has grown in the last twenty years. [Although related

by topic (housing shortage), each sentence makes its own separate point with no link to the

sentences before or after. The result is a group of related yet separate ideas instead of one

coherent paragraph.

•Limited investment in the housing sector makes it practically impossible to allocate

issue here. A small group of city officials has laid out a new plan to combat the crisis. [Each

separate fact now flows into the next, creating a coherent whole.]

•--Samuel Nunn, "Role of Local Infrastructure Policies and Economic Development

•Reducing drag in an aerospace vehicle is an important design consideration with financial

and operational consequences. Poorly designed rocket fuselage scan triple fuel and launch

costs. Drag increases stress on key joints. This proposed project will develop a model to

reduce aerodynamic drag on theRX100.

aerodynamic drag on the RX100.

•In 1912, the German chemist von Laue hypothesized that in a crystal x-ray,scattering

patterns are related to atom spacing. A series of experiments demonstrated the wave nature

of x-rays and the periodic arrangement of atoms. Spots on a photographic plate provided

the proof for the hypothesis.

•In 1912, the German chemist von Laue hypothesized that in a crystal x-ray,scattering

nature of x-rays and the periodic arrangement of atoms. Spots on a photographic plate

•This broadcast packet switching should be distinguished from the store-and-forward variety.

To handle the demands of growth, our system can be extended using repeaters for signal

regeneration, filters for traffic localization, or gateways for internet work address extension.

•--R. M. Metcalfe and D. R. Boggs, "Ethernet: Distributed Packet Switching for Local

Networks" (modified)

• In the following paragraph, the topic sentence is supported in examples that illustrate,

support, and clarify the main point.

•Use narration to establish a series of events that tells the reader what happened.

•Narration follows a chronological pattern of development.

•It is a convincing mode of paragraph development to the extent that it tells a coherent story.

•This pattern or time line is usually very easy to understand.

•Ideally, an image should contain a region of high-intensity pixels that form the target,and a

low-intensity background. To find the target region, the algorithm first samples the images in

overlapping windows and sums the pixel intensities contained in each window. The window

with the highest sum is assumed to contain the target, and the average of the remaining

windows is assumed to be indicative of the background level. Thus, subtracting the average

of the window sums from the highest window sum provides a measure of the target strength

over the background noise level. If an image does not contain a target, then the different

between the highest sum and the average sum will be very small. The difference will also be

small for images containing faint targets and high levels of background noise.

are continuously being produced in the bone marrow. Neutrophils, one type of white blood

cell, travel in the blood stream to areas of invasion, attacking and ingesting pathogens.

Macrophages, or "big eaters," take up stations in tissues and act as scavengers, devouring

pathogen sand worn-out cells. Natural killer cells directly destroy virus-infected cells and

cells that have turned cancerous. When lymph nodes are actively involved in fighting an

invasion of microorganisms, they fill with lymphocytes.

•Global climate change resulting from the accumulation of greenhouse gases, for example,is

likely to have significant health effects, both direct and indirect. An average global

temperature rise of 3-4°C, predicted for the year 2100 by the Intergovernmental Panel on

Climate Change,will greatly increase the number of days in the United States with

temperatures over 38°C(100°F), with a resulting sharp rise in heat-related mortality. Deaths

would occur primarily from heat strokes, heart attacks, and cerebral strokes. The very

young, poor, and elderly, as well as those with chronic cardiovascular and respiratory

diseases, are most at risk. During the two-week heat wave of July 1993 in the eastern

United States, 84 people died in Philadelphia alone as a result of the higher temperatures.

Definition